Originally Posted by
Tomo
HI
Try using and old pad with a caliper piston wind back tool [just to keep the piston 90 degrees to hole .
There may be little room I suspect
U can use either silicon brake slide lube [very slippery] or rubber grease .
If there is a piston boot u can either install boot on the piston first then install boot into caliper and push piston in .
The other way is to install seal and boot into caliper apply compressed air to enter via the bleeder[seal with rag ]
The piston needs to be then installed as the air that's escaping is expanding the boot over the piston ..
tomo