[Aussie Mike]

Good idea using bolts up through the floor Rob. It's pretty hard to round off a cap screw so you cant undo it. I'm a fan of button head cap screws as they have a nice rounded edge that doesn't catch on things.

On my chassis all of the seat mounting holes are well away from the ground. The body tub sits on top of the chassis and The seats bolt through to the C section chassis cross members.

Cheers