Olds64 and Don71 - sounds like you were both zeroing in on the answer.....I got a separate reply from Sparky at sparkyscarbs.com. He identified the fitting as a "7/8-20 long". This meaning 7/8" with SAE 20 threads and having the external gasket/seal. He sent me to Carburetors Unlimited for the fitting and I plan to call them tomorrow morning for availability (
www.carburetion.com). Thanks again!