I would bolt them to your seat rails since they are stronger than the floor and that way there won't be bars of steel sticking out the bottom of your car.
Or if you have any VW seats that are falling apart you could use the bottom of them to weld to the celica seats to take up the height differance and also retain the stock slider funtion.
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I love my money pit, uhm, err, I mean my car.
1969 beetle in the works... 2.0 type 4 DTM...
2004 Suzuki GSX-R 1000
crashed
www.volksport.net Volksport Kfer Gruppe