I'm looking at a Jazz bass on ebay, serial number MN516194, apparently made in the early nineties. Anyonw know if this bass is poplar or alder? Also, I've noticed it doesn't have the same plate with the controls I've typically seen on Jazz Basses. I thought this plate was separate to the pickguard? And would it be possible to return it to the typical aesthetics? Anyway, thanks for the help .