Powdercoating M42 Valve Cover

[achtungE30]

I'm in the process of getting my valve cover and intake manifold powdercoated. The shop called me today to tell me that the inside of the valve coverhas a plastic splash shield held in by bolts which can be removed and another small panel that is riveted in. He is afraid to proceed with sandblasting it prior to coating it because the fine grains of sand may get stuck in the crevices.  He also claims that because it is still in place there is probably oil still in there.

To anyone who's done this before, does the riveted plastic pieces pose any purpose or is it simple german overengineering? Is it safe to remove? Is there an alternative? I would rather not paint the pieces but am considering it as a last case scenario if so.

[Tonyb]

The M42 has a sealed ventilation system, and this part keeps the oil from getting sucked in to the top hose. Take the plastic piece off first. It only has a few small bolts holding it in. If you don't the blasting media will get stuck in there and ruin your engine. I planned on taking the same route as you, but I decided to paint it myself.

[M42boy]

Yeah, you definately need to remove anything like that before sand-blasting.  Any reason you have to sand blast it before painting?  I don't think these were painted from the factory, so I think you could probably clean it well (I had mine dipped in an electrostatic cleaner) and then have it powder coated.  

I want to have mine powder coated in a black wrinkle finnish.  How much are you being quoted to PC the VC and IM?