I love my 87 FXRS. I am stumped in trying to find a rear caliper. I sripped mine while re-attaching the hydrolic line and it can´t be repaired.Harley says the part is obsolete and there isn´t one available anywhere in the US.My question to anyone in this group is. Can my early 87 system be converted to a late 87 FXR system? And what type of aftermarket is the best?