So I'm dropping a new long-block into my 818 donor. What a process! As I get closer and closer to being "done" it seems that more little tasks/problems crop up and "done" doesn't seem to be any closer.
May I thus propose a corollary the more famous relativity theory: the Theory of Relativity for Car Mechanics:
The closer you are to the completed project, the more time it takes to complete each step
Yesterday it was a sudden halt to replace a wonky clutch master cylinder (surprise!). Today it was exhaust flange holes that magically shrunk so that I couldn't get a bolt through them (exhaust had to come back off again, then I had to drive home to fetch a drill...), then a coolant leak from a banjo that I know I torqued properly when the engine was on the stand...