Man, that's pretty. From what info. I've gathered ..... 7000 and 9000 series came out in '78.Thanks for getting the shell construction right. I recently asked Yamaha tech support about the wood. The birch is from Hakkaido Island in northern Japan. The mahogany is Phillipine.
Yamaha experimented with wood combo's with the 7000 series. '78/'79 Camellia/Phil.Mahog. '80 Birch/Phil.Mahog. '81 on Agathis/Phil.Mahog.
The 8000 series got the 9000 series split lug when Yamaha went long high tension lug and the 9000 became the Recording Custom (1980). And it got the Birch/Phil.Mahog. shell from the 7000 series. Great rock drums.