Hi Verne
Thank you for the additional info on what to look for. Looks like it is what we originally thought...an Impala SS Convertible but not an original 409. Most of the drivetrain is looking like it is 1964. In addition to that, the new things you said to look for...Exhaust is not welded, ballast resistor has solder, not converted from manual trans. And here's the numbers:
Block 3844422 - 324 - X
Heads 3819333 - GM3 - CFD - 289
Intake 3767578
Trans Pan C0904N
Trans Tail 3789080
Rear GM T3 - 3726899 - E2366
Carb 01-552 - 6-1518
Alternator! 1102174 - 1E17
Still a cool car, but I don't think we are going to be retiring any time soon...
Oh, yeah...and

too!