Iirc pats car runs 9 inch wheels and the original box was a hewland box . The deter wide body car runs 14 inch rear and 12 inch front . The un1 gearbox is used in many reps they struggle above 300lb but there is a guy in Coventry that rebuilds them with a strong kit for gt40 reps that take the power. Most reps stand out like a mr2 Ferrari lol it is quite a thing to build a good rep as 99% of the kits are modified copy which are quite shocking