I may have screwed up ....more than once

We've ALL been to the screwup penalty box! This is going to be a very long (and very hilarious - see post #15) thread if we all list our screwup history.
The mention of a mechanical oil pressure gauge is a "must". I like to have a mechanical oil pressure gauge in the engine compartment so I can check for oil pressure immediately and not have to take the time - and risk engine damage - to have to check oil pressure on an interior gauge.