the 2 isometry classes of irreducible [8,5,4]_8 codes are:

code no       1:
================
1 1 1 1 0 0 0 0
3 2 1 0 1 0 0 0
5 3 1 0 0 1 0 0
2 4 1 0 0 0 1 0
7 5 1 0 0 0 0 1
the automorphism group has order 42
and is strongly generated by the following 5 elements:
(
1 0 0 
5 7 3 
1 1 1 
, 1
, 
7 0 0 
6 6 6 
1 2 6 
, 0
, 
7 3 6 
5 1 6 
0 2 0 
, 1
, 
0 0 2 
4 7 6 
1 0 0 
, 0
, 
7 5 1 
7 3 5 
5 3 1 
, 0
)
acting on the columns of the generator matrix as follows (in order):
(2, 7, 6)(3, 8, 4), 
(2, 4)(3, 7)(6, 8), 
(1, 4, 6)(2, 3, 7), 
(1, 3)(2, 6)(4, 7), 
(1, 8)(2, 7)(3, 6)
orbits: { 1, 6, 3, 8, 7, 4, 2 }, { 5 }

code no       2:
================
1 1 1 1 0 0 0 0
3 2 1 0 1 0 0 0
7 3 1 0 0 1 0 0
6 5 1 0 0 0 1 0
2 6 1 0 0 0 0 1
the automorphism group has order 168
and is strongly generated by the following 4 elements:
(
1 0 0 
0 3 0 
3 6 1 
, 2
, 
7 0 0 
1 4 7 
6 5 7 
, 1
, 
6 0 0 
2 6 1 
4 6 5 
, 0
, 
0 0 6 
1 2 4 
2 2 2 
, 2
)
acting on the columns of the generator matrix as follows (in order):
(3, 5, 7)(4, 8, 6), 
(2, 4, 7)(3, 5, 6), 
(2, 7, 3, 4, 5, 6, 8), 
(1, 4, 3)(2, 5, 7)
orbits: { 1, 3, 7, 6, 4, 5, 2, 8 }