The generator matrix

 1  0  0  1  1  1  X  1 X^2+X  1  1 X^2  1 X^2+X X^2+X  0  0  0  1  1  1  1  0 X^2  1  1  1  1 X^2  1  1  1  1  X  X  1 X^2  X  1  X  1  1
 0  1  0  1 X^2 X^2+1  1  1 X^2+X X^2+1  0  1 X^2  1  0  X X^2+X  1  X X+1 X^2+X X^2+X+1  1  1  X X+1  X X+1  X X^2+X X^2+X+1 X^2+X+1 X^2+1  1  1 X+1  1 X^2 X^2+X+1 X^2+X X^2 X^2+X+1
 0  0  1 X^2  1 X^2+1 X^2+1 X^2+X  1 X+1  X  X X^2+X+1 X+1  1  1  1  1 X+1 X^2+X+1 X^2+1  1 X^2+X+1  0  X X^2+X  0 X^2 X^2  0 X^2+X X^2 X^2  0  1  X X^2+X X^2 X+1  X X+1  X

generates a code of length 42 over Z2[X]/(X^3) who´s minimum homogenous weight is 40.

Homogenous weight enumerator: w(x)=1x^0+249x^40+128x^42+62x^44+36x^46+16x^48+16x^50+4x^54

The gray image is a linear code over GF(2) with n=168, k=9 and d=80.
As d=80 is an upper bound for linear (168,9,2)-codes, this code is optimal over Z2[X]/(X^3) for dimension 9.
This code was found by Heurico 1.11 in 70.6 seconds.