evan326, I've used a dime to set the pad's toe-in. It's just a little more than 1 mm and it's the cheapest precision tool I have (TIC). Reads like you've performed the usual trouble shooting steps and remedies, see what happens with a bit more toe-in.

I have had one, I think, set of pads the squealed no matter what I tried and I replaced them with a new set of OEM pads (maybe Ultegra?). While that worked, explore every option before replacement.

Brad