Cant answer that Fred. I think not because that would wipe of the phosphorus coating. I don't use metal prep but probably should. I just make sure its damned clean and wipe with a good paper towel with virgin lacquer thinner until the paper towel doesn't show any dirt. Or that stupid expensive alcohol based final wash. I think that metal prep really messes with me cause I have sooo much iron in my water.
And, some of those grease and wax removers leave an oily residue. Just not sure.
Something I fight with in my head a lot.