So the tape deck in my SC-811 "Premium Sound" head unit finally died. I've been using it with a cassette adapter to listen to Sirius radio, ipod, etc. I attempted an aux-line in connection by soldering in wires to the R/L/G pins on the tape deck, but my solder gun tip was too big and I ended up just melting all the connections into each other. Needless to say, time for a new unit!

I could just get another SC-811, but I'm starting to think it would be better to get an aftermarket stereo that actually has a line-in port, even though I would lose that 1995 vintage stock look. Crutchfield and Scoshe sell wiring harnesses so you don't have to splice any wires in the dash, e.g.: http://www.crutchfield.com/App/Product/Item/Main.aspx?i=120709220&tp=2977&tab=review

But my car has 8 speakers - 4 in the doors, two tweeters in front, and two more in the back behind the rear seat headrests. Does anyone know if this adapter will only power the 4 door speakers, or all of them? Since it plugs directly into the volvo harness unit I assume it would, but I'd rather not plunk down $200 only to find out it doesn't. Should I go above 50 watts in the aftermarket stereo given the extra speakers as well?

-KLB