Timmy's tech tip # 187.
If you're still using the stock shaped-wire brake caliper pin retainers, consider switching to these 90 degree bent hitch pins. P/N 901.351.955.10.
They seemed un-obtainable, or over priced for quite a while so we were hoarding at every chance, but now you can get them at SSF for around a buck a piece.
Because they get twisted and bent everytime you install pads, we've seen several failures of the stock pieces lately allowing the pin to back out towards the wheel, in one case, nearly damaging some very expensive Fuchs alloys.
Most of the time, these better hitch pins can be quickly pulled just using your finger tips! Install is a breeze, too, as they can be installed at almost any angle.
I've been using these stainless steel pins on CRE built 944 Spec cars since around 2004 and have not had a failure yet.
Cheers!