hi, I have recently taken my car for its discs to be skimmed and just as the car was being driven out to be checked the mechanic noticed the ns calipers leaking fluid. He tried to tighten the banjo bolt however it wouldn't tighten as its threaded. I have the older billet 4 calipers from hispec and unfortunately they no longer have the back side of the calipers as they have moved to a newer design. I'm hoping to get the thread re threaded however should this fail I will need either replacement calipers or a replacement back part. Does anyone have a back part they could sell?