Nothing wrong with doing something for fun or to learn. However, given your goal of getting the car built in a reasonable time, you might just want to do an inspection on the engine as it sits. Modern EFI engines don't wear like the older carbed engines did. Better manufacturing with tighter tolerances, nearly perfect mixture control and better oils have contributed to engine lives exceeding 200,000 miles. If that engine is still tight there is no reason to slow down the build to rebuild it. It will be more than powerful enough to reach your goal of "a lover, not a fighter".

You are starting out as I see many builders do. The engine should be the last thing you build.

First, you will need it to fit everything to the car as it is built and engine rebuilds, like everything else, can drag out for months. That would basically be time wasted on the actual build of the car.

Second, you will spend a lot on the new engine build and that money may be needed to actually build the car. You will constantly be reminded how much you have in an engine that is just sitting there waiting on a car. And, you will have a brand new engine just sitting waiting to be started. I wouldn't recommend starting your fresh engine until the car is nearly finished. That way all of the heavy oils and break in lubes used during the build will stay in place to protect the machined surfaces.

IMO, the engine shouldn't be touched, as far as rebuilding goes, until the car is torn down for final paint. If yours goes like most builds, it will come apart several times before you finally drive it.

I would do a leak down test or, at the least, a compression check to check the condition of the rings and valves. If you are going to convert the engine to carb, then you could do that now and test fire the engine. You would need to do the conversion brefore the build anyhow. Hook a mechanical oil pressure gauge up and see what kind of pressure you have.

Remember, whatever that engine came out of was most likely running when it was scrapped, especially if it was wrecked.

Just my 2 cents.