Might need to get one of these world beater suspension systems out there, and show how well it works, before anyone may want to invest in it...... :slap:
Anywhere from 100" to 105" is good, and since you referred to a 40, 100" in a 40 with a 4" lift and 38's with a 6" wider track would be good [my 40 was 98"] and nice and stable.
An 80 series is 112" from memory, and 6" wider than a 40 in track already, so wider rims and bigger tyres with a big...