I've discovered that if I want a texture that only drops troopers to drop a jeep, is to add to the model= section of the aircraft.cfg model=cargo and it will then have no doors
with a jeep in it and it is converted to a jeep dropper. That works for me.

This one was originally a troop dropper only but converted to a jeep dropper:
I changed the title to read: title=AH_Fairchild C119F Vietnam Cargo
and add model=cargo in the aircraft.cfg file, Now I can choose this particular texture to drop just troops or just a jeep
(I had to duplicate the first original one and add cargo to the model section)
So it would seem that this logic would apply to any of the other troop droppers.
When I first read about the "configuration tool" in the manual, I had this notion that one could configure any of the supplied aircraft to drop troops or a jeep.