What all do I need from the 4.0 to swap the head on a 258? I plan on using my intake or possibly going up to a 2 barrel intake with bbd. Also do I buy head gasket for 4.2 or 4.0?



FrankenJeep J-10
80 body and frame
77 258 engine
79 th400 and bw1339
79 d44's with 3:54gears welded rear
36" Iroks on 15x10 rockcrawlers
Soa and shackleflip