The generator matrix

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

generates a code of length 20 over GR(64,4) who´s minimum homogenous weight is 126.

Homogenous weight enumerator: w(x)=1x^0+728x^126+5544x^127+4459x^128+1344x^133+10192x^134+33264x^135+14791x^136+39424x^140+9408x^141+35672x^142+79464x^143+27755x^144+21x^152+77x^160

The gray image is a code over GF(8) with n=160, k=6 and d=126.
This code was found by Heurico 1.16 in 2.8 seconds.