Morris Minor Owners Club

The clag will take an eternity to remove using regular oil changes.
I've found that once the sump, rocker cover and push rods have been cleaned while off the engine the oil takes a very long time to discolour.

Rocker cover cleaned; as you say a lot of gunk builds up in there. Sump not been off yet and I doubt I will clean the push-rods. These are bigger jobs than just whipping the rocker cover off.
But you never know at the next service I might just whip my rods out

Come the spring/summer service when it's fairly pleasant to be working under a car I think I'll drop the sump. It's dropping oil more than I would like anyway.

Never removed a sump before so is there anything more to it than simply taking care not to damage the oil pump/pipe and making a good job of renewing the gaskets?

Don't let it drop on your head - and don't strip the threads when refitting......

I wouldn't worry about the push rods until such time as the head needs to come off.