¡Buesnos dias, Eduardo!
I've had pretty good luck with my suppliers--LexJet and Ink Jet Art. Both have web sites and calling them I can usually get an answer to a direction to take. Don't know if either has boards for the 7600/9600, though.
In Sacramento, California, a good place is Pacific Office Equipment, 5802 Watt Ave., North Highlands, CA 95660-4754, (916) 334-7875
A couple of older HP laserjet printers were donated to a client and needed to be upgraded to make them compatible with their network. After talking to Fahdy (I think that's him), found they wouldn't work. He knew the printer in and out.
We have the Epson 2200 there for a clean and rebuild. A few years ago, he fixed it in hours when Epson was totally clueless on how to fix it. However, the Epson rep was smart enough to give us his phone number.
A number of friends have also taken their Epson printers to him and had them fix.
If anyone has a clue, it would be him. If he can't do it, I'd be hard pressed to find anyone else that might.