The fixed nature of the seats does not work for me. I made4 mine adjustable so my wife could also enjoy driving the car. In essence, I kept the sliders, made two flat brackets that mount to the frame with the through bolts FFR supplied. I welded nuts to the back side of the bracket for the seat mounting points. I'm able to move the driver sear about 3 1/2". I also used tempered Masonite to make a flat area under the seats which will of course be carpeted.

Masonite with 4 bolts passing through the frame.
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Bracket bolted to frame, and nuts ready to accept seat bolts.
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Everything ready for the seat.
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These last two pics show how much the seat can move.
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