Basic Mini-Amp install in 1990 Accord
 

I have a feeling this is a super noob question, so thanks in advance for your patience. I recently purchased a 1990 Accord with no stereo (just a hole in the center console). Instead of buying a full replacement unit, I realized that all I needed was a way to connect my phone to the speakers. I purchased one of these:

500W Car 2-Channel Mini Amplifier AMP for mp3 MP4 iPod | eBay

But I'm not exactly sure how to wire it up, although I do have access to the stereo wiring harness. I think I have three major questions:

1. Which of the harness wires should I connect to the power input?

2. Is there any reason not to connect both the respective speakers to each channel? (In other words, both the front right and back right speaker to the single right channel output).

3. Do I need to disconnect the battery before I do all of this, or will the car being turned off be enough to protect me from blowing myself up?

Thanks!

I solved this, so just in case it is of any use to anyone else, here are the answers:

1. The switched 12V is the wire that should go into the power, along with the ground. Switched means that it is off when the car is off, which is good for this purpose.

2. Having both front and rear speakers wired into their respective channels by simply soldering them together does not appear to be a problem.

3. Disconnecting the battery was not necessary. I got an assembly that connected directly into the existing stereo harness. That allowed me to wire everything up and then just plug it into the car (with the car off, of course).

Thanks for following up. It is fine to combine front and rear right together, and front and rear left together.

Your method is fine, just be careful and ensure the amp or amp power wire is fused at 10A.