I BOUGHT A USED F-75, IT IS IN PRETTY GOOD SHAPE. BUT I NOTICED THE THE DISPLAY HAD A SLIGHT WIGGLE AT THE HAND GRIP. JUST WONDERING IF SOME ONE KNEW HOW IT WENT TOGETHER AT GRIP. AND MAYBE A SAFE WAY TO TIGHTEN IT UP WITH OUT SENDING IT BACK TO FISHER. A DIAGRAM WOULD BE NICE TO SHOW HOW IT IS CONNECTED. THANKS