The kit is $15-$20, the rebuilts are $65-$70.
From what I understand, you can't scratch the sides or it will leak.
You have to have the pistons set at 10 degrees (forward?) or it will squeak.
I said screw it, if they leak or squeak, it will be someone else's fault and they can fix them.
Is the piece of mind worth $50?. It is to me.
Also, if I screwed it up, I would be spending $20 on the kit and then $70 more on the rebuilts. I didn't feel confident enough to risk it. Besides, the bolts were rusted into the caliper.