How do I get information for an older Fosgate Audionics unit?

Is Rockford Fosgate affiliated with Fosgate Audionics?
How do I get information for an older Fosgate Audionics unit? 

Rockford Corporation is not affiliated in any way with the pre-2000 Fosgate Audionics products or company. The company, originally based in Heber, Utah, and founded by Jim Fosgate, was purchased by Harman International in 1991. It was merged with their Citation brand in 1995. Because of contractual obligations, the Fosgate Audionics brand was returned to Jim Fosgate in 1999. In 2000 Fosgate Audionics became a Rockford Corporation brand.

Support and service for all products manufactured prior to 2000 should be direct to RJPC. (Robert J Popham) in an agreement with Harman Int., took over all service for Fosgate Audionics, Citation and some JBL/AudioAccess products.

Pre-2000 Fosgate Audionics Models:
3600, 3601, 3602, 3604 3608, 3610
Model One, Model Three and Three A, Model Four, Model Five

Citation Models:
7.0, 5.0, plus all the other Citation home theater products

Between (2000-2005), Rockford Corporation developed "Fosgate Audionics" home theater products.