Had to put new brake pads on rear discs of a SAAB 99 I owned and drove back in the '70's. I'd departed for a trip with a friend (who was a SAAB mechanic at the time) and his then girlfriend when we noted the noise of scrubbing backers. We returned to the then-closed shop (it was about 8 PM by then) where we determined they'd not yet purchased the needed 'special tool' to retract the brake pistons.

So I scrounged through their scrap pile, found a bit of channel stock I could cut & grind to shape, made 'pins' out of something else, welded it up and shaZAM! got us back on the road by about 9:15.

Like merziac related, you do what you have to to get further down the road....