Hiya, I would remove the pad then compress the piston and place the retainer on... the retainers are spring steel, and not very thick.... i have a pair somewhere, never used them... usually i take a C-clamp and compress the pistons with the old pad, the remove the old pad, insert new pad, repeat for other side and hope compressing them doesn;t push out the side i just did. Then I'd place a socket of similar length to the width of the disc and then wiggle the caliper back on.....
so long story short.... compress piston with old pad(so not to damage the piston), place new pad in, and good to go..hopefully(you are dealing with a vette after-all....nothing goes according to plan...usually)
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StingrayJim
NCM Lifetime Member #1936
Stingray's '76���������������������������� StingrayJr's '78���������������������������Lil Red '94
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