The bullet deflector on top of the cowl is the same. Front fenders are different. The cowl side pieces might be the same dimensionally but probably have some different hole locations. I've been meaning to check that.
Halftracks and scoutcars are the same overall width but because of the different powerplants (speculating here) most of the cab stuff is an inch or two different in size yet add up to the same overall width. I compared a piece of original rear scout car armor with an original piece of m2 rear armor and they are exactly the same width, I think the holes for the skate rail are even in the same location.