I've seen the 255 equivelent diameter (Yokohama Geolander AT's) on Classics before now and they fit very snuggly up into the standard arches - in this case the steering locks didn't have to be moved but that may not be the case on all Classics. The 235's will fit without modification and will improve your roadholding no end.
........we also tried the same vehicle with my 265/75x16 Dirt Devils :twisted: . We nearly tore the wing off just lowering the jack! :shock: But, damn, it looked good with 'em on!
Cheers
Eeyore