I have helped a couple friends over the years with their Gretsch kits and now I have one as well. What I have noticed is that some Gretsch's have a bearing edge that I can best describe as routered from the outside and curved with no cut at all from the inside of the shell (it seems to me that they may have been trying to match the contour of a drumhead) and it seems like I have seen this type on the 5 plies from the late 60's, but a friends stopsign badge early 70's had this type as well. The other bearing edge I have seen on the 5 ply shells seems to be a very old school round over bearing edge. I have no experience with earlier 3 ply shells so not speaking of those at all. Can anyone out there provide more info on what, when, where, etc?