Then it's a no-brainer. Bigger amp as necessary then just extend the wiring.

One thing you might want to check is what the speakers are tapped at. I've seen hacks use much higher power taps on the speakers than necessary then they turn the amp volume down because they are too loud. So the amp isn't supplying it's rated power. Make that amp work. Re-adjust the taps on the speakers then add it all up. That may give you enough so that you won't have to replace the amp.

-Hal


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