So I made a Gavril 200BX by putting the front end of the Gavril Grand Marshal on the D-Troxx 200BX... Makes the first grand marshal with an I4 engine, though that would make a rather slow marshal.. I'd say it turned out good...
His mod already includes a GM front end. Or are you just basically saying "Hey, his mod lets you do this"? If that's the case, it's already stated in his thread that you can do this, I even posted a pic of it in the thread when the update was released.