I think you have to reinforce the unibody 'rails' and crossmembers so much that you almost build a chassis under there for 33"+ tyres to not crack and ruin the body. If you've ever looked at JeepSpeed modification parts you'll know that this is common in the US and all the parts are off the shelf.
I'm with scrw though, laning doesn't have any appeal for me, I'd rather spend the time tinkering with the Jeep getting it ready for a weeks offroading somewhere new - preferably with better weather and flowing vin rouge et biere blond. (Or just playing on rocks at Seven Sisters).
Saying all that in defence of the XJ builder, after being in New Zealand in January I really fancy Toyota's latest 70 series wagon with it's 4.5 V8 turbo diesel and front and rear diff locks from the factory. Plus it's a Toyota and has a chassis. Anyone know the closest market they sell them in??
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