I run a couple of websites making the schematics for these amps easily accessible.As people download them, I'm hoping they'll respond to my request that they send me their amp's serial number for this project, and many do.Could Fender make so many PRIIs, considering they were making another 13 amp types in the range at the same time?Then Soren in Denmark started showing serial numbers on his excellent Super Champ website, recently gone off the web - some of those numbers fell in between some of 'my' PRII numbers.In addition I had automated searches running on e Bay for these 14 amp types - whenever one appeared for sale I would contact the seller, asking for the serial number.9 out of 10 did - many thanks to them for their trouble and good will.Subtract one from the other and I'll have a rough-cut figure for how many were made. PRII owners were kind enough to start sending their serial numbers in.
Then I became aware of the amazing work Greg Gagliano had been doing since the 1990s - the summary of his latest results are here - and that his research stopped just before the Rivera-era. However for this range of amps at least, I reckon it's not just a policy of withholding company-confidential information. It's no criticism of Fender to suggest that they were too busy making great amps to keep records just so some amateur can use them thirty years later.There are a handful of amp types for which I'm still running the searches because I have so little data (mainly in the solid-state range).