I found something interesting yesterday. I was looking at another later model of npr GM W50, I asked the guy at the shop where it was at if he knew anything about the transmission that it had in it and more to the point about the adapter ring between the engine and tranny. Well guess what, it had an Allison tranny and it was bolted up with out any aditional adapters or anything else. So, that means that if I can get the right part #s we maybe on to a way to put a nv4500 or something else made in the USA behind this little 3.9. I am going to try to get more info about these engine rings from GMC truck or Isuzu.
Dieseltim
