Any info is welcome as I may attempt this at some point.

I would not do it. Parkerizing  is a poor  substrate.

From what I know of cerakote I don't think it will work.

Something like Moly Resin, however would work very well if the parkerizing is new or you can get it sufficiently degreased.

Be fine...as long as you media blast first. Cerakote really need to tooth. Aluma Hyde will work fine if you can't.

It depends on the method.  

Park job thats been oiled-  You might be able to get it setup to work but tough to say.  


Park job where you blast the part, clean it,  park tank it, post tank wash, bathe in acetone, then cerakote-  Works very well.   But this also works well with Duracoat, Norrels, and even alumahyde.    This route is best used with Norrels though.  


This is the next step on my MP5SD build in the HK sub forum.  I am waiting on my brownells park solution to get here to move forward.