On our OTK kart we use 2 standard struts on the left and 1 purpose built bent OTK strut on the engine side (it has 2 attachment points on the carrier and seat). It clears the exhaust nicely. I mount them on the carrier at the top of the axle and the next point just ahead of the axle and then towards the top of the seat. It creates more side bite allowing the inside rear to lift better and rotate thru the corner rather than sliding the rear thru the corner.
I would second what Kirk said. We did exactly the same thing when we ran OTK. Its pretty challenging with the Rotax, but it can be done. The adjustable strut that bolts into the side of the bearing cassette fits pretty nice, but they break too easily. Need to watch them closely.
KartLift Kart Stands
DeepSeat Kart Seats
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