Good quality masking tape on engine block?

[Llay R. Rac]

I cleaned and painted my engine, (I-6) while in the truck with manifolds and water pump removed. I cut pieces of the type of water proof wallboard used for shower and tub enclosure to match the shape of the manifolds and water pump, drilled the holes and mounted them using silicone sealer and short bolts. i wanted to use aluminium plate but didnt have any on hand.
for your oil pan maybe get a junk pan to install while cleaning.