The generator matrix

 1  0  0  0  1  1  1  0  0  X  1  1  1  X  1  0  X  X  X  X  0  1  1  1  1  0  1  1  1  0  1
 0  1  0  0  X  1 X+1  1  1  1  1  1  0  X  0  X  1  0  1  1  1  X X+1  X  1  1  0  X X+1  1 X+1
 0  0  1  0  0  0  0  X  1  1  1 X+1  1  1 X+1  1 X+1  1  X  X  X X+1  1  X  X  0  X  1  X X+1 X+1
 0  0  0  1  1 X+1  X X+1  1  0  X  1  1  1  X  X  X X+1 X+1  1  X  1  1 X+1  1  X  X  X  0  1  X

generates a code of length 31 over Z2[X]/(X^2) who´s minimum homogenous weight is 28.

Homogenous weight enumerator: w(x)=1x^0+74x^28+96x^30+31x^32+48x^36+6x^44

The gray image is a linear code over GF(2) with n=62, k=8 and d=28.
As d=28 is an upper bound for linear (62,8,2)-codes, this code is optimal over Z2[X]/(X^2) for dimension 8.
This code was found by Heurico 1.16 in 0.0101 seconds.