My '97 850 wagon has the base SC710 radio head unit. Can I connect an SC811 or SC815 just by plugging it in? I know the base unit is like 80 watt and the premium ones are like 100 watt or so, hence my concern.

Thanks

 

Yes. It's just a simple pull the old one out, plug the new one in. Don't worry about the watts. You wont blow speakers.

 

Generally speaking, speakers "blow" from too little power far more often than they do from too much. I'd also be willing to bet that the speakers they put in the cars with the basic stereo are the same speakers they use in the 'premium" stereo.