Long story short, I'm doing 6bt with SAE 3 flywheel housing and spicer 3053a tranny into 72 GMC longbed. I'm using a 5.9 6 speed flywheel, I have confirmed it is SAE 3 compatible and it is the largest ring gear diameter that will fit in a SAE 3 housing. No one and I mean no one seems to be able to help me figure out what starter I need. We do know that the dodge NV 4500 starter has the right bolt pattern and the bendix ejects to the proper depth, however the bendix gear is not big enough around to engage the teeth with the flywheel. I need to find out what medium duty truck used a 5.9 cummins with a SAE 3 flywheel housing and a manual transmission. If i can figure this out then I can source the starter with a part number. Most of the medium duty truck yards seem to be idiots in our area and not able to help me. Thanks