Place your go kart on it’s trolley and place 2 steel pipes (or something similar) underneath either side of the kart to lift the chassis off the trolley slightly.
Place the seat into the appropriate spot on your go kart and use a heavy item to hold seat base flat and parallel with chassis rails (battery or otherwise).
Measure 550mm from the inside of the front chassis rail to the front of the seat leg support, adjust the seat, if necessary, to reach this measurement.
Holding the nib with the pliers, mark out holes from chassis seat support on to each side of the seat.
Remove the seat from the go kart and use your battery drill, with an 8.5mm drill bit,  to drill through the newly marked holes into the seat (both sides).
Place the seat back into the go kart and secure it in place with the heavy item used in step 1.
Using your black wedge spacers, close the gap between chassis’ seat support and and the outside surface of seat.
Use a 13mm socket in a ratchet and 5mm Allen key or T-Bar.
Remove the steel pipes supporting the kart and let the kart sit directly on the trolley.
Using the appropriately sized black spacer, close the gap between the seat and the chassis seat support on the underside of the kart.
Drill the bottom holes in seat with an 8.5mm drill bit
Using a 13mm socket in a ratchet and 5mm Allen key or T-Bar.

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