How do you go about hooking a stock stereo to an aftermarket amp? Is the purpose of speaker level inputs so you can use the speaker outputs on the head to hook directly to the amp? Is this best or should I tap in someplace else. I'm a newbie to stereo gear, but I have the install done up to this point. Also, this is for my 97 Civic beater, not my S.
Thanks.

 

You've got it right. The speaker-level inputs on your amp are so that you can connect the speaker output wires from a head unit to the amp w/o using RCA's.

 

But if your head unit has 'preamp outputs' , I'd suggest using those. The head unit will generate a bit less heat, and you'll put the amplification in the amp, where it willl likely be of better quality. Another consideration, though, is that the low level ( aka preamp out ) signals to the amp may be susceptible to noise if your grounding & sheilding is incorrect.