How to install the Recessed Motorcycle Wheel Chocks
First, locate the frame cross members. If your trailer has 24" spacing, you must use the 24" wheel chock. If it has 16" frame spacing, you must use the 16" wheel chock. These chocks MUST mount directly between the floor cross members, with each end sitting on top of the cross members. I cut the hole with a standard 7.25" circular saw. Just be careful not to hit the frame. (As I get older, I need more light- that is a 250 watt HPS street light!)
Drill six 3/8" holes. The ones at each corner should go through the frame of the trailer. The two middle holes will go into the floor only. These will have large "fender washers" on them to pull the floor up to the wheel chock. The wheel chock is supplied with 5/16" carriage bolts, nuts and washers. All you need it two people, one under the trailer with a wrench, and one above, holding the bolt down.