Got the chance of a tractor , got spec sorted out but tyres seem a minefield , got the chance of Michelin 650/85r38 rear 600/70r28 which I presume can be deflated a lot or 710/70r42 rear 600/70r30 trelleborgs which can’t be deflated as much , tractor weighs around 9 and bit tons , what’s folks thoughts , thanks