The generator matrix

 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  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  X  1  1  1  1  1  1  X  1  1  1
 0  X  0  0  0  X  X  X a*X  0  X a*X a*X a*X a*X  X a*X a^5*X  0  X  0 a^4*X a^2*X a^4*X a^2*X a^3*X a^2*X a^6*X  X a^3*X a^4*X a^2*X a*X a^2*X  0  0 a^3*X a^5*X a^2*X a^4*X a^4*X a^3*X a^6*X a*X a^4*X a*X a*X a^2*X a^3*X a^3*X a*X  X  X  X a^6*X a*X a^2*X a^6*X a^6*X  X a^2*X a*X  0
 0  0  X  0  0 a^6*X a^5*X a^4*X a^4*X  X a^3*X a^6*X  0  X a^5*X a^2*X a*X a^6*X a*X  0 a^2*X a*X a^5*X a^2*X a^3*X a^4*X a^3*X a^5*X a^6*X a^5*X a^6*X a^5*X a^2*X  0  0 a^2*X  X  X a*X a^6*X  X a^6*X a^2*X a^6*X a^3*X a^3*X a^6*X a^3*X  0 a^2*X a^6*X a^2*X  0  0 a^4*X a^3*X a*X a^4*X a^5*X a*X a^6*X  0  0
 0  0  0  X  0  X a^5*X a*X a^3*X a^2*X a^6*X  0 a^5*X  X a*X a^4*X a^4*X a^4*X a^4*X a*X  X  0  X  X a^5*X a^5*X a*X  0  X a^5*X  0 a^3*X a*X a*X a^5*X a^6*X a^4*X a^4*X a^3*X  0 a^6*X a^2*X  X a^2*X a*X a^5*X a*X a^5*X a^3*X a^3*X  X  0  X a*X  0 a^6*X a^6*X a^4*X a*X  0 a^4*X a^6*X  0
 0  0  0  0  X a^6*X a^3*X a*X a^5*X a*X a^2*X a^2*X a^3*X  0 a*X  0 a^2*X a^4*X  X a^3*X a^4*X a*X a^3*X  0 a^6*X a^4*X  X  0 a^2*X a^6*X  X  X a^4*X  0 a*X a^6*X a^5*X  X a^4*X a^5*X  X a^4*X a^6*X a^4*X a^2*X a^6*X a*X a*X a^5*X a*X a^2*X a^6*X  X a^6*X a^6*X  0  0 a*X a*X  0 a^4*X a^5*X  X

generates a code of length 63 over F8[X]/(X^2) who´s minimum homogenous weight is 392.

Homogenous weight enumerator: w(x)=1x^0+133x^392+1099x^400+2170x^408+2793x^416+3297x^424+3584x^427+3787x^432+50176x^435+4256x^440+175616x^443+4354x^448+4263x^456+3136x^464+2198x^472+952x^480+259x^488+70x^496

The gray image is a linear code over GF(8) with n=504, k=6 and d=392.
This code was found by Heurico 1.16 in 39.1 seconds.