Pretty self explanatory. They are 1/4" longer than OEM. Need to purchase 1/4" plexiglass, and longer bolts. The mounting holes have a metal sleeve, that can either be ground down, or as i did, ground out so the spacer lays flat. The clearance is slightly larger than a razor blade... should be sufficient. The right side sensor can be used also on the left side. It will be about a week before I get the rest of the suspension work completed and I will update on performance and function.