And how many engines have you had apart, Mr. Labs?
Three. two BMC a-series, one 850cc mini unit with a blown head gasket, and another that needed conversion to run on unleaded fuel (valve seats on old engines get buggered up without lead, so it was easiest to replace the entire head as one unit). Also the engine of an old honda 125 (forget the exact bike but it was found in a ditch). That one wouldn't turn over no matter what, so we pulled it apart to find it entirely full of mud. Scrapped it.
Sure, there's basic stuff like changing the oil and flushing the radiator that anyone can do, but fully disassembling an engine is better left to people who are qualified.
Like people who can operate a ratchet? It's not hard, you can't really put the wrong part in the wrong place. A camshaft will not fit inside a carburator no matter how hard you push.
Anyway, I think we were talking about those "amiga" things?