I found a spot on the Fender web site that has an offer
for old schematics and service manuals, including Sunn.
I paid $5.00 for a copy of my Sunn Concert Bass
schematic and service info. See it at:
http://www.fender.com/a/01appx.html
Also, I need to cross a transistor, 2N4304, jfet, and
I haven't been able to find a replacement yet. Got any
ideas?