This is probably the most ridiculous thing you've ever heard... But what is to stop me ditching the in-door speakers and all that rubbish and bunging a pair of standmount speakers on my parcel shelf (solidly affixed of course) and using a DC-DC converter to power a DC accepting power amp? that may require some modification to get it to work... like gutting out the PSU of an amp that uses around 14.4V internally and using the battery power, all within my abilities. Just wondering if it would be a total waste of time or just.. undeniably cool I've got an old pair of tannoy MR's sitting idle. They are nice compact little rear speakers which I think would be the ones to fit the bill in this instance. I've also got an old Rotel RA01 and a porked Cambridge audio A1 (volume knob dud and not replacable). I guess I could nick the power amp out of the CA, but I think it runs at 18V which would be a problem, but not an unfixable one.