Convert to GAS

I think most of the lower end from the diesel would work in a gas engine. The diesel uses a forged crank that uses different bearings than the gas engine cast crank.

All in all, I think you would be ahead just getting a complete gas engine and rebuilding that rather than trying to convert the diesel. Or rebuild the diesel--they are much more fuel efficient, although also much more expensive to rebuild than a gas engine, especially if you have to rebuild the injector pump. If you decide to use a gas engine, make sure to get all the throttle linkage--it is different on the diesel.

I am looking for a rebuildable 172 diesel near Eastern Washington to replace the 144 in my 641D. Where are you? I am not familiar with Manteca... Good luck with your project.

The block should be the same 173 ci, but you'll obviously need the gas engines manifolds,head, and internals - pistons etc. It would be cheaper and simplier to find a gas engine that is complete and bolt it up.