Is it safe to paint the inside of yo oil pan

 

Why would you even do that?

 

Probably not a good idea. Over time the oil will break down the paint causing it to peel and can cause serious damage to the engine, I seen it happen where a friend painted the lifter valley of a sbc and a few years later when we tore it down due to spun bearings there was no paint left in the lifter valley.

 

+1
If you're painting the outside of the pan, just set it on the ground upside down and spray it.