I was messing around with the rear seat riser and seat cushions, and decided I should see how the seat belts interfaced with all this. I ordered seat belts from Hooker Harness, with Schroth rotary buckles.

I went to install the front seat lap belts, and noted that there was a very wide bushing for the bolt that attaches the lap belt to the aircraft structure. This bushing required a much wider slot than is provided by Van's design for the belt attachment. You can see how the too long bushing is forcing the two parts of the mount apart.

I pondered simply removing the bushing, but I wasn't sure why it was there, so I didn't want to risk affecting the integrity of the belt attachment. I called Hooker Harness, and explained the situation. They were very aware of the "issue", and recommended using a file to make the bushing narrower. They explained that the bushing was very important, as it ensured that the belt attachment hardware would be free to rotate around the bolt. If the hardware could not rotate around the bolt the loads would be carried by one edge of the belt webbing causing it to be cut and fail if a large load was placed on it.

The bushing looks to have been made from a piece of aluminum tubing, with the ends expanded to keep it from falling out of the hole. I figured out that it was easy to take away material using a ScotchBrite wheel, with a piece of wood holding the other end of the bushing parallel to the seat belt hardware. I removed enough material to make the bushing about 0.020" longer than the attachment hardware.

Now the seat belt hardware fits nicely as Van intended it too.