Help me diagnose a screeching rear wheel (with visual aides)

[Hotwatermusic]

I've noticed a pretty nasty screeching sound coming from the rear wheels latetly. It's there whether I'm on the brakes or not. Now, it's worse when I do hit the brakes, and seems to present the most from the driver's side rear, but I don't know if it only_seems_that way because it's the side I can hear better with the window down.

So I took the driver's side rear wheel off today to have a look at the brakes. The pads are fine, plenty of life left (see pic). But when I took the pads out and turned the wheel by hand, I could still hear the screeching sound. Oddly though, the sound only presents when I turn the wheel forward. It's damn near silent when I turn the rotor in reverse.

I looked inside the caliper as best as I could, and noticed the interior-side piston's boot was torn (see pic). I can't figure how that would cause the noise I'm hearing, but it will need to be fixed nonetheless. My other problem is I can't get the caliper completely off because I can't get access to the second bolt that is holding it on. The one on the bottom. There is precious little room to even get a box wrench on it, and forget about a ratchet. What's the trick, or tool, used to get into that tight space and remove that bottom bolt? With the caliper off I think I could a better idea of what's causing that screech.

So, nasty nails-on-a-chalkboard sound coming from the rear brake rotor (even with pads removed), and seemingly only when turning forward. I made sure the rotor is clearing the shield. Anyone have any idea what I am dealing with? Thanks!

[Flieger]

Betcha your handbrake mechanism is sticking on that side. It is a drum setup on the interior of the rotor, near the hub.

[DanielDudley]

Just from the look of that, I would say it is time to rebuild or replace calipers, hoses, and pop the rotors to look at the E brakes. Could be the E brakes, but you know that you have a problem right there.

Can't really tell, but the rotors are probably decent, gauging by the pads.

[Kemo]

lots of interesting parts in the E-Brake system that could be rubbing...

[moneymanager]

You haven't got a rock between the rotor and the shield have you? This happened to me once, the screeching lasted all the way from Carmel to Santa Barbara before I finally figured it out.