John, Bob, Daniel, & Sonny - Thanks for all your help!!! The consensus weighs heavy on John's "Molded Silicone Ring" - inner. I am also glad to see John's plug pic. I think I'll hang on to mine.
I have never pulled the pan from the TH350 Trans. Can anyone tell me if this particular pan is stamped. And...has anyone out there ever restored a pan as pitted as this one? And... just in case, is EBay the only place to find a born with/NOS SB pan?
Thanks again gentleman!