Hi, Ive just purchased a quadrant shower from a supplier selling on that well known auction site, the problem is the holes in the glass door are 10mm and the roller locating lugs/bolts are 6mm so even when the roller bracket is screwed up tight the bracket actually slides about on the glass!! seems to me there is a spacer needed or they are the wrong size rollers/holes in glass? I've spoken to the supplier who tells me this is normal but it don't look right to me?? any suggestions???