...at a car show last summer...
...at the drive-in...
The engine was free- I turned it over by hand first. But I thought top end lube would do only good as those piston rings had to be dry as a bone after all that time, so I pulled all the plugs and used a big syringe sans needle to shoot diesel into the cylinders with no mess, and dumped a bit more down the intake, then let it sit for three days before flushing that out and firing it up. I doubt there was any sort of build-up or dirt or anything- just dry.
I'd keep that Pinto as-is; that 2.3 engine is probably the best part of the car, they are very good engines. It's getting old enough now to get some interest as a nice original survivor. If I had big dreams for a diesel Pinto or V8 or whatever I'd start with one that needs work anyway.