the 13 isometry classes of irreducible [8,3,4]_3 codes are:

code no       1:
================
1 1 1 1 1 2 0 0
1 1 1 0 0 0 2 0
1 1 0 1 0 0 0 2
the automorphism group has order 32
and is strongly generated by the following 5 elements:
(
1 0 0 0 0 
0 1 0 0 0 
0 0 1 0 0 
0 0 0 1 0 
2 2 2 2 2 
, 
2 0 0 0 0 
0 2 0 0 0 
1 1 0 1 0 
1 1 1 0 0 
2 2 2 2 2 
, 
2 0 0 0 0 
0 2 0 0 0 
0 0 0 2 0 
0 0 2 0 0 
0 0 0 0 2 
, 
2 2 2 2 2 
0 0 0 0 1 
0 0 0 1 0 
0 0 1 0 0 
0 1 0 0 0 
, 
0 1 0 0 0 
1 0 0 0 0 
0 0 1 0 0 
0 0 0 1 0 
0 0 0 0 1 
)
acting on the columns of the generator matrix as follows (in order):
(5, 6), 
(3, 8)(4, 7)(5, 6), 
(3, 4)(7, 8), 
(1, 6)(2, 5)(3, 4), 
(1, 2)
orbits: { 1, 6, 2, 5 }, { 3, 8, 4, 7 }

code no       2:
================
1 1 1 1 1 2 0 0
1 1 1 0 0 0 2 0
2 1 0 1 0 0 0 2
the automorphism group has order 4
and is strongly generated by the following 2 elements:
(
1 0 0 0 0 
0 1 0 0 0 
0 0 1 0 0 
0 0 0 1 0 
2 2 2 2 2 
, 
1 0 0 0 0 
0 2 0 0 0 
2 1 0 1 0 
1 1 1 0 0 
0 0 0 0 1 
)
acting on the columns of the generator matrix as follows (in order):
(5, 6), 
(3, 8)(4, 7)
orbits: { 1 }, { 2 }, { 3, 8 }, { 4, 7 }, { 5, 6 }

code no       3:
================
1 1 1 1 1 2 0 0
1 1 1 0 0 0 2 0
2 2 0 1 0 0 0 2
the automorphism group has order 8
and is strongly generated by the following 3 elements:
(
1 0 0 0 0 
0 1 0 0 0 
0 0 1 0 0 
0 0 0 1 0 
2 2 2 2 2 
, 
2 0 0 0 0 
0 2 0 0 0 
1 1 0 2 0 
2 2 2 0 0 
0 0 0 0 2 
, 
0 1 0 0 0 
1 0 0 0 0 
0 0 1 0 0 
0 0 0 1 0 
0 0 0 0 1 
)
acting on the columns of the generator matrix as follows (in order):
(5, 6), 
(3, 8)(4, 7), 
(1, 2)
orbits: { 1, 2 }, { 3, 8 }, { 4, 7 }, { 5, 6 }

code no       4:
================
1 1 1 1 1 2 0 0
1 1 1 0 0 0 2 0
2 2 1 1 0 0 0 2
the automorphism group has order 8
and is strongly generated by the following 2 elements:
(
1 0 0 0 0 
0 1 0 0 0 
0 0 1 0 0 
0 0 0 1 0 
2 2 2 2 2 
, 
0 0 0 0 1 
2 2 2 2 2 
0 0 0 1 0 
0 0 1 0 0 
1 0 0 0 0 
)
acting on the columns of the generator matrix as follows (in order):
(5, 6), 
(1, 5)(2, 6)(3, 4)
orbits: { 1, 5, 6, 2 }, { 3, 4 }, { 7 }, { 8 }

code no       5:
================
1 1 1 1 1 2 0 0
1 1 1 0 0 0 2 0
2 1 0 2 1 0 0 2
the automorphism group has order 12
and is strongly generated by the following 3 elements:
(
1 0 0 0 0 
0 0 1 0 0 
0 1 0 0 0 
0 0 0 1 0 
2 2 2 2 2 
, 
0 0 0 1 0 
0 0 0 0 1 
2 2 2 2 2 
1 0 0 0 0 
0 1 0 0 0 
, 
2 2 2 2 2 
0 0 0 1 0 
0 0 0 0 1 
0 0 1 0 0 
1 0 0 0 0 
)
acting on the columns of the generator matrix as follows (in order):
(2, 3)(5, 6), 
(1, 4)(2, 5)(3, 6), 
(1, 5, 3, 4, 2, 6)
orbits: { 1, 4, 6, 3, 5, 2 }, { 7 }, { 8 }

code no       6:
================
1 1 1 1 1 2 0 0
2 1 1 0 0 0 2 0
2 1 0 1 0 0 0 2
the automorphism group has order 12
and is strongly generated by the following 4 elements:
(
2 0 0 0 0 
0 2 0 0 0 
0 0 2 0 0 
0 0 0 2 0 
1 1 1 1 1 
, 
1 0 0 0 0 
0 1 0 0 0 
0 0 0 1 0 
0 0 1 0 0 
0 0 0 0 1 
, 
1 2 2 0 0 
0 0 2 0 0 
0 2 0 0 0 
0 0 0 1 0 
0 0 0 0 1 
, 
1 2 0 2 0 
0 0 0 2 0 
0 2 0 0 0 
0 0 1 0 0 
2 2 2 2 2 
)
acting on the columns of the generator matrix as follows (in order):
(5, 6), 
(3, 4)(7, 8), 
(1, 7)(2, 3), 
(1, 7, 8)(2, 3, 4)(5, 6)
orbits: { 1, 7, 8 }, { 2, 3, 4 }, { 5, 6 }

code no       7:
================
1 1 1 1 1 2 0 0
2 1 1 0 0 0 2 0
1 2 0 1 0 0 0 2
the automorphism group has order 24
and is strongly generated by the following 5 elements:
(
1 0 0 0 0 
0 1 0 0 0 
0 0 1 0 0 
0 0 0 1 0 
2 2 2 2 2 
, 
1 0 0 0 0 
0 1 0 0 0 
1 2 0 1 0 
2 1 1 0 0 
2 2 2 2 2 
, 
1 2 2 0 0 
0 0 2 0 0 
0 2 0 0 0 
0 0 0 1 0 
0 0 0 0 1 
, 
0 0 1 0 0 
2 1 1 0 0 
1 0 0 0 0 
2 1 0 2 0 
1 1 1 1 1 
, 
1 2 0 1 0 
0 0 0 1 0 
1 0 0 0 0 
0 0 2 0 0 
1 1 1 1 1 
)
acting on the columns of the generator matrix as follows (in order):
(5, 6), 
(3, 8)(4, 7)(5, 6), 
(1, 7)(2, 3), 
(1, 3)(2, 7)(4, 8)(5, 6), 
(1, 3, 4, 2, 7, 8)(5, 6)
orbits: { 1, 7, 3, 8, 4, 2 }, { 5, 6 }

code no       8:
================
1 1 1 1 1 2 0 0
2 1 1 0 0 0 2 0
2 2 0 1 0 0 0 2
the automorphism group has order 4
and is strongly generated by the following 2 elements:
(
2 0 0 0 0 
0 2 0 0 0 
0 0 2 0 0 
0 0 0 2 0 
1 1 1 1 1 
, 
0 2 0 0 0 
2 0 0 0 0 
0 0 1 0 0 
2 2 0 1 0 
2 2 2 2 2 
)
acting on the columns of the generator matrix as follows (in order):
(5, 6), 
(1, 2)(4, 8)(5, 6)
orbits: { 1, 2 }, { 3 }, { 4, 8 }, { 5, 6 }, { 7 }

code no       9:
================
1 1 1 1 1 2 0 0
2 1 1 0 0 0 2 0
2 2 2 1 0 0 0 2
the automorphism group has order 32
and is strongly generated by the following 5 elements:
(
1 0 0 0 0 
0 1 0 0 0 
0 0 1 0 0 
0 0 0 1 0 
2 2 2 2 2 
, 
1 0 0 0 0 
0 1 0 0 0 
0 0 1 0 0 
1 1 1 2 0 
0 0 0 0 2 
, 
1 0 0 0 0 
0 0 1 0 0 
0 1 0 0 0 
0 0 0 1 0 
0 0 0 0 1 
, 
1 2 2 0 0 
0 2 0 0 0 
0 0 2 0 0 
0 0 0 1 0 
0 0 0 0 1 
, 
2 2 2 1 0 
2 2 2 2 2 
0 0 0 0 1 
2 1 1 0 0 
0 0 1 0 0 
)
acting on the columns of the generator matrix as follows (in order):
(5, 6), 
(4, 8), 
(2, 3), 
(1, 7), 
(1, 8)(2, 6)(3, 5)(4, 7)
orbits: { 1, 7, 8, 4 }, { 2, 3, 6, 5 }

code no      10:
================
1 1 1 1 1 2 0 0
2 1 1 0 0 0 2 0
2 1 0 2 1 0 0 2
the automorphism group has order 8
and is strongly generated by the following 3 elements:
(
2 0 0 0 0 
0 0 2 0 0 
0 2 0 0 0 
0 0 0 2 0 
1 1 1 1 1 
, 
2 1 1 0 0 
0 1 0 0 0 
0 0 1 0 0 
0 0 0 2 0 
1 1 1 1 1 
, 
0 1 0 0 0 
1 0 0 0 0 
2 1 1 0 0 
1 2 0 1 2 
0 0 0 0 2 
)
acting on the columns of the generator matrix as follows (in order):
(2, 3)(5, 6), 
(1, 7)(5, 6), 
(1, 2)(3, 7)(4, 8)
orbits: { 1, 7, 2, 3 }, { 4, 8 }, { 5, 6 }

code no      11:
================
1 1 1 1 1 2 0 0
2 2 1 1 0 0 2 0
2 1 2 1 0 0 0 2
the automorphism group has order 16
and is strongly generated by the following 4 elements:
(
2 0 0 0 0 
0 2 0 0 0 
0 0 2 0 0 
0 0 0 2 0 
1 1 1 1 1 
, 
1 0 0 0 0 
0 0 1 0 0 
0 1 0 0 0 
0 0 0 1 0 
0 0 0 0 1 
, 
0 2 0 0 0 
2 0 0 0 0 
0 0 0 2 0 
0 0 2 0 0 
0 0 0 0 2 
, 
0 0 2 0 0 
0 0 0 2 0 
2 0 0 0 0 
0 2 0 0 0 
0 0 0 0 2 
)
acting on the columns of the generator matrix as follows (in order):
(5, 6), 
(2, 3)(7, 8), 
(1, 2)(3, 4), 
(1, 3)(2, 4)
orbits: { 1, 2, 3, 4 }, { 5, 6 }, { 7, 8 }

code no      12:
================
1 1 1 0 0 2 0 0
1 1 0 1 0 0 2 0
1 1 0 0 1 0 0 2
the automorphism group has order 384
and is strongly generated by the following 9 elements:
(
2 0 0 0 0 
0 2 0 0 0 
0 0 2 0 0 
0 0 0 2 0 
1 1 0 0 1 
, 
2 0 0 0 0 
0 2 0 0 0 
0 0 2 0 0 
1 1 0 1 0 
0 0 0 0 2 
, 
2 0 0 0 0 
0 2 0 0 0 
0 0 2 0 0 
1 1 0 0 1 
1 1 0 1 0 
, 
2 0 0 0 0 
0 2 0 0 0 
1 1 1 0 0 
0 0 0 2 0 
0 0 0 0 2 
, 
1 0 0 0 0 
0 1 0 0 0 
0 0 0 1 0 
0 0 1 0 0 
0 0 0 0 1 
, 
1 0 0 0 0 
0 1 0 0 0 
2 2 0 0 2 
2 2 2 0 0 
2 2 0 2 0 
, 
2 2 2 0 0 
0 0 1 0 0 
1 0 0 0 0 
0 0 0 2 0 
0 0 0 0 2 
, 
0 0 0 1 0 
2 2 0 2 0 
0 0 2 0 0 
1 0 0 0 0 
0 0 0 0 2 
, 
2 2 0 0 2 
0 0 0 0 1 
1 1 0 1 0 
0 0 2 0 0 
1 0 0 0 0 
)
acting on the columns of the generator matrix as follows (in order):
(5, 8), 
(4, 7), 
(4, 8)(5, 7), 
(3, 6), 
(3, 4)(6, 7), 
(3, 7, 5, 6, 4, 8), 
(1, 3, 2, 6), 
(1, 4)(2, 7), 
(1, 5, 2, 8)(3, 4, 6, 7)
orbits: { 1, 6, 4, 8, 3, 7, 5, 2 }

code no      13:
================
1 1 1 0 0 2 0 0
1 1 0 1 0 0 2 0
2 1 0 0 1 0 0 2
the automorphism group has order 32
and is strongly generated by the following 5 elements:
(
2 0 0 0 0 
0 2 0 0 0 
0 0 2 0 0 
0 0 0 2 0 
2 1 0 0 1 
, 
2 0 0 0 0 
0 2 0 0 0 
0 0 2 0 0 
1 1 0 1 0 
0 0 0 0 2 
, 
2 0 0 0 0 
0 2 0 0 0 
1 1 1 0 0 
0 0 0 2 0 
0 0 0 0 2 
, 
1 0 0 0 0 
0 1 0 0 0 
2 2 0 2 0 
0 0 1 0 0 
0 0 0 0 1 
, 
0 1 0 0 0 
1 0 0 0 0 
0 0 0 1 0 
0 0 1 0 0 
0 0 0 0 2 
)
acting on the columns of the generator matrix as follows (in order):
(5, 8), 
(4, 7), 
(3, 6), 
(3, 4, 6, 7), 
(1, 2)(3, 4)(6, 7)
orbits: { 1, 2 }, { 3, 6, 7, 4 }, { 5, 8 }