Would anyone here know if and how I can switch a 2002 Sundance Optima from the standard 50 amp to a 60 amp connection so that I can have the pumps and heat on at the same time? In the manual it says it is a "minor circuit board modification that can be performed by the dealer" " title="Rolling Eyes" />

I believe the "minor circuit board modification that can be performed by the dealer" is simply a matter of changing a jumper setting to enable 60A logic instead of the factory preset 50A logic. As you say this will let you run both pumps and the heater at the same time.

It may be best if you pay your dealer to come out and do this for you - it shouldn't be expensive as it's literally a 2 minute job. If you attempt it yourself and get it wrong it could work out very expensive indeed, or even worse be an electrical safety issue.

Forgot to mention but of course it goes without saying that your electrical service (wire size) must be able to support a 60A load before making this change.