Seatbelts or not?

I know this Thread is a month old but, like the others have said, mount the lap part to the floor and not the frame. Some buckets only have 6 or so bolts mounting the body the the frame. Saw a picture from the early 2000's of a t bucket hit from the front. The body actually was ripped off the frame. You don't want to be sandwiched between the belt bolted to the frame and the body trying to move forward. Also, with a 4 point harness, I am pretty sure you want to mount the harness which straps over the shoulders as high or higher than the shoulders. I've seen the upper harness straps attached to a center tube on a rollbar. I've also see then mounted lower but in cars with several feet of open space behind the front seat. The harness strap angles back several feet to the mounting point and does not drop straight to the floor behind the seat. Others with racing experience can get more into the reasons...