what trans adapter is this?

have a vintage speed gems trans adapter part number sg 56 what the hell does it fit?

 

Can you post a photo of it?

-Lee
Atomic Radio
www.atomicpinup.com

 

Is the trans side a big circle?? I have a 1950's chart here showing an adaptor with the number "56" as fitting Pontiac to early Ford; the chart is from a retailer and contains part numbers obviously from different sources but not labeled as to manufacturer.

 

And...FWIW, "Speed Gems" was a line of "Arrow Auto Parts"