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  X  X  X  X  X  X  X  X  1  1  1  1  1  1  1  1  1  X  X  X  X  X  1  6  6  6  6  0  X  6  1  6  0  1  X  0  X  X  X
 0  6  0  6  0  6  3  3  3  0  0  6  6  0  6  3  3  3  0  0  6  6  0  6  3  3  3  0  0  6  6  0  6  3  3  3  0  0  6  6  0  6  3  3  3  0  6  6  6  0  3  3  3  0  0  6  6  0  6  3  3  3  0  6  6  6  0  0  6  6  6  3  6  0  3  0  3  6  0  0  6  6  6  6
 0  0  6  3  3  6  0  6  3  0  6  3  6  3  0  0  6  3  0  6  3  6  3  0  0  6  3  0  6  3  6  3  0  0  6  3  0  6  3  6  3  0  0  6  3  6  3  6  0  3  0  6  3  0  6  3  6  3  0  0  6  3  6  3  6  0  3  0  3  6  0  0  6  0  6  6  3  0  3  0  3  3  6  0

generates a code of length 84 over Z9[X]/(X^2+3,3X) who´s minimum homogenous weight is 168.

Homogenous weight enumerator: w(x)=1x^0+228x^168+4x^171+4x^180+6x^186

The gray image is a code over GF(3) with n=756, k=5 and d=504.
This code was found by Heurico 1.16 in 0.778 seconds.