Same size tires and 5+2's on all four and 1" spacers for the back for an even track width. That'll put you at about 54". 4+3's will put you at about 56". Having ran about every width found that 54" is enough, it's stable. Went as high as 57", it was super stable but too wide for me. Was rubbing trees with the front tires and it just wasn't necessary. FWIW