Thread: Cleaning top end, where does it stop?

Hey all,
I am in need of some wisdom
My 99 D1 v8 was starting to show signs of head gasket and valley gasket issues, so apart it comes.
I've been pretty anal about cleaning everything and now that I've had a peek under the valley gasket it's a bit filth.
Previous owner was running without a thermostat for God knows how long, probably same time they last changed the oil...
Anyway I had no intentions of touching the bottom end since I dont have means to remove the engine at home.
Is it ok to stop at the heads and rebuild or can I clean the valley without having to strip further than the valley without consequences? I would hate for crud to fall down and have to mess about with timing.
Also I'm assuming that I should clean the sump and dont know if I'll need a new oil pump. Look easy enough from under the car, any thoughts or tips?
This is my first project car, in case you hadn't guessed. I need all the help I can get haha.
Any tips or criticism welcome.

So with the valley cover off, a bit of throttle cleaner went a long way. Looks a lot better.
Is this a safe place to stop and put the top end back together? Obviously i still have the other side to do.
20200209_183239.jpg
How clean do the valves have to be on the head? The surface is clean but a little corrosion around the coolant passages which is flat.
20200209_183359.jpg