Hey so I plan on swapping an M1008 CUCV cab on my 85 K20, both are automatics. However, the M1008 cab is diesel and my current cab is not. Is there a difference in the firewall or transmission humps? Newbie question, sorry I'm new to auto restoration, this is my first vehicle. Its a 1980 cab currently with a mid 80s CUCV cab as replacement.