The nylon comes in a 1/2 bushing and then above that it comes in washers. Three washers are needed to span the length of the aluminum spacer. The 5/8 washers have a hole which accepts the aluminum spacer perfectly. For the 3/4 inch I had to drill out the senter hole to about 5/16 to accept the alumimum spacer into the 1/2 nylon bushing and then put three 3/4 washers over that. I used the 5/8 spacer on right wing and 3/4 on left wing. This gave both wings the same clearance and angle of deflection. I don't know why the left wing required a larger spacer, but to ensure the bolt didn't hit on the outboard hinge, it required the extra 1/8 inch.