That is the machine gun plate we were looking for!� excellent.� The bellcrank is also MB.� The number on the support gusset is an ACM #.� American Central Manufacturing made the tubs/sheet metal parts for Willys up until 3A production.� I'm not super familiar with ACM Willys # information for dating the Willys.� On WWII tubs, I believe Type 1 tubs had very sharp angle looking gusset supports.� Type 2 tubs are late war. The gusset supports on Type 2 are more rounded like a 2A and 3A.
Engine history is easiest to discover by knowing the block serial #.� This is a stamped number on the engine boss.� The engine boss with serial # can be found in one of two places...
--Just below the water pump.� There is a flat spot on the engine block.
OR
--Just behind where the original oil filter is mounted.� There is usually an oval shaped flat spot on the block.
Be careful when removing rust or paint from these bosses.� The stamping can be very faint if the block has been re-surfaced.� Don't GRIND away.� Use a combo of soft wire brushes, fluids, 220, 320 sand paper, etc..�
This is the best way to date the block.� The #s may not be there anymore...for a number of reasons.� If they are gone, there is almost no way to verify that the engine block is original to this Willys.
Your head is surely a MB, GPW, or VEC 2A head.� This makes me hopeful the engine is also WWII, but we won't be able to tell from the engine castings you have uncovered.� Find those serial #s!!

I don't want you to go away, but FBill has pointed out the other military sites that can be very helpful while doing your research.� Go there, but always come back to us here at the 3A.� We are all Willys enthusiasts.� We like all things flat fender.� We also happen to be the most friendly Willys forum on the net!!

Tim