HELP! HAVE 67 FASTBACK. BEFORE I TOOK IT APART, THE REAR BUMPER FIT FINE. NOW WE ARE PUTTING HER BACK TOGETHER, & THE REAR BUMPER WANTS TO TURN IN TOWARDS THE TAILLIGHT PANEL. WE ARE USING THE SAME BRACKETS, BOLTS, ETC. I EVEN HAVE THE FOUR CRUSH WASHERS, I ASSUME THEY WORK LIKE SHIMS. WE HAVE TRIED CHANGING THE CRUSH WASHERS TO DIFFERENT BOLTS, DOUBLING UP ON THEM, ETC. NOTHING SEEMS TO WORK. LET ME KNOW IF YOU CAN HELP! THANKS