Thanks for the well-wishes and guidance fellas. I expect to send it in, so as to be able to register it (despite it being only an "optional" piece and not actually factoring into anything).
It then occurred to me that although it was being talked about, it wasn't actually pictured...so, I text-searched checked the handy #911 catalogue and sure enough, no other appearance in the thread elsewhere either, so, since it arrived, here you go:
1967 Topps Disc test proof (cyan/yellow)
|