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

generates a code of length 99 over GR(64,4) who´s minimum homogenous weight is 673.

Homogenous weight enumerator: w(x)=1x^0+1624x^673+6440x^674+1848x^675+2520x^678+896x^679+3913x^680+13832x^681+23352x^682+5824x^683+6552x^686+3136x^687+6440x^688+18032x^689+31080x^690+6496x^691+7560x^694+5677x^696+18088x^697+28392x^698+6048x^699+8456x^702+3136x^703+5922x^704+16520x^705+25424x^706+4872x^707+14x^712+49x^720

The gray image is a code over GF(8) with n=792, k=6 and d=673.
This code was found by Heurico 1.16 in 20.4 seconds.