Got mine from C&G. Be sure to measure the length you need. I learned the hard way.
http://www.julianos.com/seat_belts.html Great people to deal with.
On the Julianos web site they have an example of their stiff arm 3-point seat belt installed in a 41 sedan delivery in their (How To Section).How do you guys attach the upper shoulder belt mount? There isn't much metal there, and I'm not sure it would hold in a head-on collision. After a collision is a little late to know if they will hold. It seems like lap belts securely mounted would at least keep from being thrown out of the car.