Jules, I empathise with you on this matter. When I first thought of having a go in the car classes, I looked at a Suzuki Jimny with the idea of ditching the front propshaft and removing the front differential. Them I became aware of rule K in the SSRs, i.e. 'Any four wheel drive vehicle modified to operate in two wheel drive is prohibited. Vehicles originally supplied in two wheel drive only from a model range including four wheel drive versions will be eligible'. So that was the end of that idea

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I didn't particularly want a saloon car; most are FWD and I didn't want to spend loads of time repairing floor pans, suspension turrets, etc, etc. I don't have the time, space, or inclination. A beefy chassis and suspension seems just the ticket

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What seems odd, taking the X-90 as an example is that the 2WD is eligible, but if the 4WD is converted to the same spec as the 2WD, the previously 4WD is still not eligible.
With regards to a GV2000 currently competing, I believe this vehicle was competing before the rule change so this competitor was allowed to carry on competing, but with the proviso that if he sold the vehicle, the new owner would not be allowed to enter MCC trials with it. I stand to be corrected on this.
I'm not totally clued up on car classes; but, taking a class 8 car that was constructed from a 4WD chassis, yet with one-off bodywork, rear wheel drive, 2WD gearbox; would that be allowed to enter an MCC trial