Get 1/4 inch bar stock (4 of them), like at Tractor Supply.

Bolt bars to floor – into original holes – use original bolts.

Put seat (with tracks) on top of bars, mark where the holes in the tracks are on the bars, remove seat.

Un bolt bars from floor.

Drill holes where the track hole marks are.

Put short bolts through the underside of the bars facing UP into the sky.
Tack so they do not spin.

Bolt bars back in car with studs facing UP.

Now you have 4 studs sticking UP through the carpet, put the seat (with tracks) on these studs.

Fasten seats to floor with washers and nuts.

Cosmetic Tip:

Lift up the carpet first, bolt the bars directly to the steel floor.

Put carpet back in place, nick carpet with razor where studs are,
 studs pop up through carpet.

End result - Nice & Clean.