I have the original harness bar that an former MC driver had made.
Remove the seat belt guide and the shoulder belts work really well.
I attached the two lap belts to the OEM seat attachment points. You do have to change the grade 10 OEM mounting bolts with longer ones, also grade 10.
The fifth belt was a puzzle. I manufactured a 1/8"x1" bar that bolts to the forward seat mounting points on the floor and mount the fifth belt to that. I ended up removing the thigh pad adjustment mechanism since I always have it pushed towards me anyhow. I still use a rubber sheet on the seat. This keeps the shoulder and fifth belts from chafing the leather.
These are early install pictures.
