Joe D. was working on this for me - but if he is no longer at SGC, did anyone else there continue with this request?
Brian (or whomever is doing this now),
Would it be possible to add a T206 Chicago Amer. Master set to the registry (all known front/back combinations)?
I have a compiled a spreadsheet using info taken from several sources (net54, t206.org, and SGC pop reports) that I could forward to you if it would help.