first off - meet betty
this is what many ppl will se when trying to figure how / where to mount a seat
you, ve got two m10 studs at the front and two m10 threads at the rear. what i did was make up two rail going left to right on the car with tubes welded in for the rear bolts to pass thru and machined "cups" for the front studs. After measuring the "square" made by the bolt holes in the seat runners, i measured it all up and welded machined bosses into the rails, with m8 studs for the rails
(sorry for the grind marks etc - they were dont in my lunch break!!)
the rail were then painted and bolted into the car
the seat runners were then loosely bolted down (NOTE: locking nuts - you dont want these coming loose!!)
and then finally the seat was bolted in to set the width of the runners and these were all tighten in. add harness and voila!
(sorry the pic is on its side!!!!)
any questions comments - please add - il be happy to help