...in that after taking all day to prep, clean, then fit and button up a new sump on my engine, that after filling up and turning it over there's a clatter in there, so i have to do it all again?

Surely it should warrant at least one tool thrown across the garage? But I'm looking forward to figuring out and doing it again!

I can go one better than that and can totally understand you joy.

Bought a puma 1.7 engine to go in my Anglia, all installed, then ran it, found front crank oil seal was leaking. Easy gob, me thinks. But no, took crank pulls off, new seal in, pulley back on. All fine. Start her up, runs for 2 seconds and then won't start again. As the engine has no key ways on crank or cams, the pulley had slipped (manual did not say to fit a new stretch bolt). ,put it back together with new bot, did run but a bit rough. No confidence in the engine, suspected bent valve,

I have actually enjoyed fitting another engine (£90 for the engine was cheaper than a gasket set !) and in the mean time sorting out some cooling hose routing issues, adding an idle adjuster to the throttle bodies and sorting out the makeshift exhaust. I also took the opportunity to fit an rx8 box whilst I was at it.

The big bonus is that I have a spare engine that, once the car is on the road, I can take apart and have a go at porting and polishing it :-)