After I tried to press the piston once with the heat shield I ended up removing it. Thats when I realized I hadn't previously marked the position of the piston. I'm lucky that the orientation of the piston is marked onto the old pads, or I'd be completely screwed.

I have some picks that I ground the ends off of for putting the boot on. They are rounded, so they don't puncture the boot itself. I'm about to go and try to get these aligned right again. I'm still apprehensive about how hard I should be torquing the c-clamp when I'm pressing them. I don't want to damage the piston.

Thanks for the continued help guys.