Just looked at the bottom of my Studio IV amp, based on your 9(?) year old comment. I have a SN (?) there on the bottom of my Studio IV amp...
Yeah man, not many know about these special amplifiers. Mine have ousted some serious competition over the years. Are your serial numbers on the bottom or back of the amp? Rumor has it there was a "signature" edition with the serials on the bottom (which is where mine are) but I am skeptical this is true. If you pull them out of the rack you should take a few photos!
Evan