The generator matrix

 1  0  0  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1 2a 2a+2 2a^2+2  1  1  1  1 2a^2  1  1  1  0  1  1  1  1  1  1 2a^2+2a  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1
 0  1  0 2a^2+2 2a 2a^2+2a  2 2a^2+2a+2 2a+2 2a^2  1 2a^2+a+2 a^2 2a^2+3  3 2a^2+2a+3 2a+3 2a^2+2a+1 2a^2+1 2a+1 a+2 a^2+2a+2 2a^2+3a+3 a^2+3a a^2+3a+1 3a^2+2a+3 3a+2  a 3a^2+2 3a^2+2a 3a^2+3a+3 3a^2+3a+1 3a^2+a+1 3a^2+3a a^2+a+2 a^2+a+3  1  1  1 3a^2+a+2 3a a^2+a a^2+2a+2  1 2a^2+a+1 3a+1 2a^2+3a+1  1 3a^2+2a+2 2a^2+a+1 a+3 3a^2+3a+3 3a^2+3a+2 2a^2+3a+2  1 2a^2+a 3a^2+2 3a^2+a+2 2a^2+3a+1 a^2+a+3 3a^2+3 3a^2+2a+1 a^2+2a+1 3a^2+2a+1 3a^2+2a+3 a^2+1 3a^2+2a+2 a^2+3a+3 a^2+3a+2 a^2 a^2+3a+3 3a^2+a+3 2a^2+2
 0  0  1  1  a a^2 3a+3 a^2+3a a^2+3a+3 a^2+2a+1 a^2+2a+3 3a^2+2a+1 a^2+1 a^2+3a+1 a^2+a a+1 a^2+2a a+2 2a^2+3 2a^2+2a+2 2a^2 2a^2+2 2a+2  2 2a^2+2a 2a 2a^2+3a+3 3a^2+a+1 a^2+3a+2 3a 2a+1 3a^2+a a^2+2 2a^2+3a a+1 a^2+3 3a^2+3a+1 2a^2+3a+3 a^2+2a 2a^2+1 3a^2+a+2 a^2+1 2a^2+3 2a^2+a+2  a 3a^2+2a+3 3a^2 2a+3 3a^2+2a+2 3a+1 2a+3 3a+1 3a^2+3a+2 2a^2+a a^2+2a+1 3a^2+2 3a^2+a+3 a^2+a+1 3a^2+a+2 a^2+3a+1 a^2+3a+3 a+3 3a^2+a 3a^2+2a 2a^2+3a+2 2a^2+2a+1 3a+3 2a^2+a a^2+2a+2 2a^2+a+2 2a^2+a+3 2a+2  2

generates a code of length 73 over GR(64,4) who´s minimum homogenous weight is 495.

Homogenous weight enumerator: w(x)=1x^0+4760x^495+11837x^496+8736x^497+1792x^498+560x^500+15512x^503+31983x^504+15960x^505+3528x^506+1120x^508+22792x^511+34111x^512+18032x^513+2352x^514+1904x^516+25032x^519+40845x^520+18200x^521+3080x^522+7x^544

The gray image is a code over GF(8) with n=584, k=6 and d=495.
This code was found by Heurico 1.16 in 25.7 seconds.