Har har! These are hilarious!

I have:

forgotten to put lifters in an engine until dropping the pushrods in thru the (already torqued) head;

swapped heads and tried to start the engine without having installed a rocker assembly;

drained a transmission and then added 4 qts of oil to the crankcase (not on a Volvo);

replaced a clutch but forgotten to install the throwout bearing;

elevated a 122 using only 4 oem tire changing jacks;

spent about an hour on a subfreezing day trapped under a 122 with some fingers pinned under a transmission that had fallen (once the fingers were numb they ripped out easily, though messily);

removed a B18 from an engine compartment with 2 people / 4 hands and no sort of lift;

installed a B20, ditto;

driven for several years without a pilot bearing.

There are others even more stupid, but I'm not telling.

Hee hee!

Later -