Ooo
Glen, Some rails have the figure 8 plates and some have the heavier duty--(vs GC3 style) steel floating nut plates in the rails. I was under the assumption they were 1s and 2s based on that but I really have never really known the difference in a 1 vs a 2.
If you look at it this way, there never really was a GC2, it was a GC1 in all reality. The changes made to the 1 that made it a 2 was first off, no more painted skirts, the 2 has rosewood paint stained rail skirts, it also had the GC3 bronze coated leg levelers and bronze coated ball tray metal trim. Every other change that everyone thinks that makes up a GC2....caome out on the GC1 first, floating rail capture nuts, adjustable leg levelers, ashtray corner castings....everything....was in production on the GC1 first, that's why the GC2 only sold from 74'-76' then the GC3 came out....with the same GC1 rail hardware and pocket casting....only then, the pocket casting matched the bronze feet and ball tray trim....and first introduced the bolt on rail skirts.
PS, i just consider all GCs to be 1s, 1-3s, 3s, 4s, & 5s.