I've got new pads and rotors to put on, and it's not going well! I got the little square tool from the auto parts store to compress the cylinder with a socket wrench, and I got it spread a lot farther than it was. But it's still not enough. I'm just a few mm shy of being able to get the caliper over the pads but I cannot get it spread anymore. It turns easily enough but it doesn't seem to go in anymore. I tried cracking the bleeder valve but that didn't do anything either. Is there some kind of trick? Or something wrong with my caliper? It's so close to fitting but yet so far...

 

The caliper could have seized. Rear caliper failure is common on these cars. Also, if you don't use the parking brake, it is even more likely to seize.

Get Napa Eclipse or Cardone Ultra calipers.

 

Well I managed to get it. The rubber boot was binding up and I think maybe that was keeping it from going in? I pried it loose a little and sprayed some silicon lube around it so it would slide and then I was able to get the caliper in all the way. Phew.

 

Just know this lifespan of back brake pads might be problematic, and next time, it's time to go new/rebuilt back calipers and hoses. And a power bleed.