Installed the gas tank, reconnected all electrical connections. Pulled spark plugs and rotated the crank 360 degrees just to be sure I didn't screw up the valve timing. If I had a valve/piston interference I wanted to find out by hand rotating things rather than finding out when I cranked the starter. (Yeah, I'm a worrywart).
Engines I have done: Volvo 122S, Datsun 280Z, BMW R75/5, R90S, R90/6; they all survived my rebuilds.
But there is always that start up anxiety. Back when I was building electronic stuff in my Ham Radio days, the last test was the "smoke test". Spend weeks soldering and bench testing circuits, but on the final day, plug it in. Wait for smoke. No smoke? Good.
First start on an engine rebuild has that kind of anxiety for me; I haven't done enough to have confidence.
Old joke: What is the essential ingredient in all electrical circuits? Ans. "Smoke".
Why, because whenever the smoke gets out, it doesn't work any more.
Class Charlie Fire! Commander!
Tomorrow, heat the oil pan, pull fuse #4
and crank it a while. Run an exhaust hose out under the garage door, then put in the fuse and see what happens. Look for leaks.