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  2  1  1  1  1  1  1  2  1  2  1  2  1  1  1  1  1  2  1  2  1
 0  2  0  0  0  0  0  0  0  0  0 2a 2a+2  2 2a+2  2 2a+2 2a 2a+2 2a+2 2a  0 2a+2 2a  2  2 2a+2 2a 2a  2  0 2a 2a 2a 2a  0 2a+2 2a+2 2a  0 2a 2a+2  2 2a+2 2a+2  0 2a  2  2  2 2a+2  2  2  2  2 2a+2 2a 2a  2  0  0  0  2
 0  0  2  0  0  0  0  2  2  2 2a  0 2a 2a+2 2a+2 2a+2 2a 2a+2 2a+2  2 2a  0  2  0 2a  2  2  2 2a  0 2a 2a 2a 2a+2  2  2 2a  2  0  2 2a  0 2a+2 2a  2  2 2a+2  2 2a+2 2a 2a+2 2a 2a  0  0  2 2a  0  2  2 2a+2  2 2a
 0  0  0  2  0  0  2 2a+2 2a 2a 2a 2a  0 2a+2 2a 2a 2a+2 2a 2a+2  0 2a+2  0 2a 2a+2  0  2 2a 2a  0 2a  0 2a+2 2a+2 2a  2  0  0 2a+2 2a+2 2a+2  2  0  2  0  0 2a  0  0 2a  2 2a  2 2a+2 2a+2 2a+2  2  2 2a  0  0 2a  2  0
 0  0  0  0  2  0 2a+2  0  2 2a 2a+2 2a 2a+2  0 2a 2a  2  0  2 2a 2a  2 2a 2a+2 2a  0  0  0  0 2a+2 2a 2a+2  0 2a+2  0  2 2a+2 2a+2 2a+2 2a  0  2  2  2 2a 2a+2 2a  2  0 2a  0 2a 2a 2a+2  0 2a+2 2a  2 2a  2  0 2a 2a
 0  0  0  0  0  2  2  2 2a+2  2  2  0 2a+2  2 2a 2a+2  2  2 2a+2  0 2a+2  2 2a 2a+2  2  0 2a+2  2  2 2a+2 2a+2 2a 2a  0  0 2a+2 2a 2a+2  2 2a 2a+2  2 2a 2a+2 2a+2  2  0  2 2a+2 2a  2 2a+2  2 2a  0 2a 2a 2a 2a 2a 2a+2  0 2a+2

generates a code of length 63 over GR(16,4) who´s minimum homogenous weight is 168.

Homogenous weight enumerator: w(x)=1x^0+240x^168+351x^172+72x^175+444x^176+360x^179+411x^180+1680x^183+447x^184+3600x^187+390x^188+4392x^191+330x^192+2184x^195+360x^196+312x^200+288x^204+222x^208+162x^212+69x^216+51x^220+15x^224+3x^228

The gray image is a code over GF(4) with n=252, k=7 and d=168.
This code was found by Heurico 1.16 in 97 seconds.