I have an early Birdy that uses the nylon blocks to pinch the seat tube, instead of the current method that's used. I'm going to fillet braze a rear rack and want to use the original mounting points. I understand that the rear rack is supposed to attach to the quick release, but it's not clear how. Does anyone have closeup pictures of both sides of the connection with a rack installed? I'm new here, so can't post pics yet. Thank you.