The generator matrix

 1  1  1  1  1  1  1  1  1  1  1  1  1
 0  2  0  0  0  2  2  2 2a  0  2 2a 2a
 0  0  2  0  0 2a^2+2 2a^2+2a+2 2a^2+2a 2a^2+2a  2 2a+2 2a^2+2  0
 0  0  0  2  0  2 2a^2+2a+2 2a 2a+2 2a^2 2a^2+2  0 2a^2+2a+2
 0  0  0  0  2 2a^2+2 2a+2 2a 2a^2+2a+2 2a 2a^2 2a^2 2a+2

generates a code of length 13 over GR(64,4) who´s minimum homogenous weight is 64.

Homogenous weight enumerator: w(x)=1x^0+567x^64+2170x^72+3668x^80+10164x^88+229376x^91+10388x^96+5810x^104

The gray image is a code over GF(8) with n=104, k=6 and d=64.
This code was found by Heurico 1.16 in 4.42 seconds.