The generator matrix

 1  0  0  1  1  1  1  1  1  1  1 (a+1)X  1  1  1  1  1 (a+1)X  1  X  1  0 (a+1)X  1  1  1  1  1  X  1 aX  1  1  1  X  X  1  1  1  1  1 (a+1)X  1  1  1  0  1  1  1  1  1  0  1  0  0 (a+1)X  1  1
 0  1  0  0  X aX  1 (a+1)X+a a+1  1 (a+1)X+1  1 (a+1)X+1  a aX+a+1 aX+a+1 X+a  1 a+1  1 X+a  1  1 X+1 aX+1  a  1 (a+1)X+a+1  0 (a+1)X  1 (a+1)X  X aX+a+1  1  1 (a+1)X+a+1 aX+a+1 X+a aX aX+1  1 (a+1)X aX+a (a+1)X (a+1)X X+a (a+1)X+a+1  0 aX+a X+1  1 X+1  1  1  1  a (a+1)X+a+1
 0  0  1  1 (a+1)X+a (a+1)X+a+1 X+1 aX+1 (a+1)X+1 a+1  a X+1  0 aX aX (a+1)X+a  a aX+a+1 (a+1)X+a+1 (a+1)X+a a+1  X X+1 aX+a+1 aX+1 X+a X+a aX+a+1  1 aX+1 X+a+1 (a+1)X+a aX aX+a aX  a aX+1 aX  X (a+1)X+1 (a+1)X+a+1 aX+1 a+1 X+a+1  1  1 X+1  X X+a aX+1  1  X aX+a (a+1)X+a  a aX (a+1)X+a (a+1)X+a
 0  0  0 (a+1)X  0  0 (a+1)X (a+1)X (a+1)X  0  0  0  X (a+1)X aX  X (a+1)X (a+1)X  X  0  X (a+1)X aX  X aX  X aX aX aX  0 aX aX (a+1)X (a+1)X  X (a+1)X  X  0  0 aX (a+1)X  X aX aX  X (a+1)X aX (a+1)X  X  0  0 aX  X  0  X  0 aX (a+1)X

generates a code of length 58 over F4[X,sigma]/(X^2) who´s minimum homogenous weight is 163.

Homogenous weight enumerator: w(x)=1x^0+780x^163+414x^164+2304x^167+963x^168+2808x^171+744x^172+2352x^175+696x^176+2160x^179+744x^180+1188x^183+462x^184+636x^187+60x^188+60x^191+3x^192+6x^196+3x^200

The gray image is a linear code over GF(4) with n=232, k=7 and d=163.
This code was found by Heurico 1.16 in 1.29 seconds.