I saw the sticky for GM paint codes but I cannot find the paint code for the engine. It is a light grey color and I want to match the original stock look. I have the engine out of my car right now and need to touch up some spots and paint the tubing in the engine bay the same color as the engine bay. Does anyone know the paint codes for the engine bay?

 

The engine bay?? Last I check the engines weren't painted

 

Not the block the sub frame/firewall

 

should be the same as the outside?????

 

You should be able to go to a paint shop and get PPG Deltron 2000 DBI. This is a single stage underhood paint, it sprays on and looks like base without clear. The DBI does not require clear and cures to a flat non gloss finish, just like the exterior color before the clear goes on. I guess it's designed to restore the factory look.
The DBC is the exterior base/clear, DBI is the underhood paint. PDF file link.
I guess this is what you're looking for, personally I'd just paint it black or body color with clear.