Mine are a whole lot like Classic69's except yellow and black. I built a frame to mount the seats on (out if 1 1/4" square tubing) bolts to original seat mounting holes. For belts i went with PEAK racing harnesses. The lap belts use the original seat belt holes. I took removed the gas tank, cut a peice of 1 1/4" square tubing that went all the way across the cab, mounted the bolts for the shoulder straps then bolted the bar to the top mounting holes from the where the gas tank was mounted.
I tried to take some pictures but my camera is screwed up...I got one decent one but then I gave up on the pics and just took a video