Ok, I have been reading other forums the last couple of nights...
I am reading that some of the caliper remanufacturers will reuse the pistons if they look ok to save money.
I have also read that the majority of binding incidents occur with the pistons getting stuck more than the guide pins.
There is also a good engineering reason that they use phenolic. I just cant remember it. lol. Temperature insulation? Or corrosion of the wet brake fluid?
Also read one guy where I guess he ended up with two mismatched pieces and the guide pin holes on both parts were 0.030" off. So no slidy good.
Anyway, I have searched and found two companies that DO replace the pistons with new units.
Centric and NuGeon
I went to the Motorcraft site and they probably do, but I cant tell for sure by the verbiage.
I am searching local sources, but they are both available on Rock Ahuto.
Im planing Centric. Have an email out asking about their warranty.