Mike O'Sullivan has set a benchmark for this with his C15A, I reckon. Mike drove it from Turkey to Normandy in 2009, which is where I met him.
Mike has since moved to the USA with his business and the C15A. In 2022 he did a Dallas Texas to Fairbanks Alaska round trip covering 10,000 miles and he does 55 on the way to a convoy and 35-40 miles an hour on the convoy.
His C15A is fitted with a 235 c.i. engine, different seats, CB radio and some more mods. I hope Mike can do a write up of the modifications he did.
