Entire right side speaker system not working
 

So, I removed my SC-816 stereo from my 1998 Volvo V70 wagon in a futile attempt to replace the bulbs since I was getting tired of turning on the interior lights to push a button on the radio at night. Long story short, I was not able to replace the bulbs and instead just reinstalled the radio and called it a day, telling myself I'd install an aftermarket when I got the chance.

However, upon powering the radio back on and entering the programming code I noticed my entire right side speaker system no longer worked. My left side however, all the way back to that tinny little speaker on the rear pillar by the hatch, worked perfectly. I removed the radio again and then reattached all the plugs as snugly as I could and still no sound out of the right side.

I only noticed 4 plugs in total to the back of my stereo, 2 wide multi-pin plugs with many colored wires coming out and then two antenna plugs. Am I missing one?

Did I blow an amp of some sort? If so, where is the amp for the right side? Any help would be much appreciated as I'm not too incredibly knowledgeable with car audio.:(

Probably a stupid question but did you ck and make sure the Balance adjustment wasn't all the way over to the left channel?

It's adjusted by pulling out the volume knob and turning; has a detent in the center of its range.