To clean the heads, a parts washer sure would be nice, but you can try some Gunk engine degreaser to get started. To clean the combustion chambers you can use a gasket scraper to knock the big chunks off then a wire brush on a drill to finish them up. For the piston tops you can also use the gasket scraper but you need to be careful not to get residue lodged between the piston and the cylinder wall. Try using a shop vac to suck up the residue as you scrape. It helps to rotate each piston up to top dead center to work on it. Also do your best not to scratch or put grooves in the aluminum piston.

It's been a while since I have worked on a disassembled engine in the car this way, so there may be some chemicals available now that would make your work easier.

For Gaskets, I have always done well with Fel-Pro, but any good quality gasket set should work. Go to a "Real" auto parts store, the one that the jobbers go to, and ask for recommendations. Ask them about the gasket sealer also. If you buy a Valve Job gasket set you will get everything you need.

Hope this helps

Pat