I've removed the front calipers, pads, caliper holder brackets and rotors. Luckily tons of material left on the pads, calipers look good (no leaks and boots not broken) and rotors in good condition. Just lots of gunk and spiders webs and such.

I'd like to now remove the large backing plate behind where the rotor was to clean and repaint. Do I have to take off the 4 large bolts from the back? Looks like it doesn't just hold on the backing plate though and I want to make sure everything doesn't fall apart when I remove those bolts. Also looks like I have to straighten out the end of a bracket that obstructs me from getting my wrench on those bolts. Does this sound right?

ok, yes everything will fall apart when you remove those bolts, but everything will bolt right back together too, the nuts are ment to be removed from the rear, just bend back the tabs, the bolt heads are irregular shaped, and not intended to be held with a wrench. the caliper mounting bracket, holds the bolts from turning.