The front area of my original 2 bbl Rochester carb has the usual rusty build-up (on the inside of the cast-iron base). I was planning on cleaning the majority of the rust off, and then coating it with POR-15 silver to seal it. Will the silver hold-up in the hot/fuel enviornment of the carburetor? I don't want the stuff to flake off and get sucked down into the manifold. Any thoughts?