I have a cast iron adapter ring for the power glide transmissions PN #3742366 date code D 3 58 Google says it fits 55-61 passenger cars and Corvettes. Seems in good condition other than needs a trip thru the glass bead machine to remove the rust scale. No obvious damage or broken out mounting holes. Worth keeping with hopes of selling it to someone doing an original restoration? What sort of value might it have? Bead blast, prime and paint (color?) or blast and leave natural finish? Thanks for any input.