The generator matrix

 1  0  1  1  1  1  1  1  1  0  1  1  1  1  0  1  1  1  1  X  1  1  1  1  X  1  1  X  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  0 a^2*X a^2*X  X a^2*X a^2*X a^2*X  0  X a*X  1  1  0
 0  1  1  a a^2*X+a^2  0 a^2*X+1  a a^2*X+a^2  1  0  a a^2*X+1 a^2*X+a^2  1  X a^2*X+1 X+a a*X+a^2  1  X  1 X+a a*X+a^2  1  X a*X+1  1  0 a^2*X+a a*X+a^2 a^2*X+1 X+a  X a*X X+1 X+a a*X+1 a^2*X+a^2  1 a^2*X+a a*X+1  1 a*X+1  1 a^2*X+a  X a*X a*X  a a*X+1  a a*X+a^2 a^2*X+a a^2*X+a a*X+a a^2*X+1 X+a X+a^2 a*X+a^2 X+a^2 a^2 a*X+a^2 a^2*X+a^2 X+a^2 X+a^2 X+a^2  0  1  1  1  1  1  1  1  1  1  1 a^2*X+1  a  1
 0  0 a^2*X  0  X  0  X a*X a*X a*X a*X  X a^2*X a^2*X  0 a^2*X  0 a^2*X  0  X  X a*X a*X  X a^2*X a*X  X a*X a^2*X  X  0  X  X a^2*X  0 a^2*X a*X a^2*X  X a*X  0 a*X  0  X  0 a^2*X a*X  X  0  0 a*X a*X a^2*X  0 a^2*X  X  0 a^2*X  0 a^2*X a*X a^2*X  X a*X  0 a*X a^2*X  X  X  0 a^2*X a^2*X  X  0 a^2*X a*X a*X  X a*X  X  0
 0  0  0  X a*X a*X  0 a*X  X  X  0  X a*X  X  X  0  0  X  X  X  0  0  X  X  X a*X a*X  0 a*X a*X a*X  X a^2*X a^2*X a^2*X  X a^2*X a^2*X  0 a^2*X a^2*X  X  X a^2*X a^2*X a^2*X a^2*X a^2*X a*X a*X a*X  0 a*X  0 a*X  0 a*X  0 a^2*X a^2*X a*X a*X a^2*X  0  0 a^2*X  0 a*X a*X a^2*X a*X a^2*X a^2*X a*X  0 a*X a^2*X  0  0 a^2*X  X

generates a code of length 81 over F4[X]/(X^2) who´s minimum homogenous weight is 236.

Homogenous weight enumerator: w(x)=1x^0+822x^236+1986x^240+201x^244+150x^248+312x^252+612x^256+9x^260+3x^272

The gray image is a linear code over GF(4) with n=324, k=6 and d=236.
This code was found by Heurico 1.16 in 2.16 seconds.