[Lynn Eades]

Rob, there is nothing wrong with being slow on the road. If I'm driving something slow, I regularly pull over to let others go by. If I'm in the car, I like to go as quick as I'm allowed.(sometimes plus a little.... Did I write that?) I then hate the inconsiderate B with 10 cars up his A with no intention of letting anyone through.
It's all about keeping left (or right) and exercising a little respect for the guy your holding up.

As far as modification goes, aside from handling issues, one of the issues with old M.V's. is braking. If you're going to increase the h.p, what are you intending to do about stopping the thing?
Some of these old vehicles were under braked at 30mph. It takes a lot more brakes to haul them up from 60mph. and they don't usually lend them selves to serious upgrading.

When I was in the army I remember seeing The brakes from an RL Bedford wrecker cooked like you wouldn't believe. It had another Bedford RL on a suspend tow. We have some steep hill ranges here. He was on a long descent and although the driver was supposedly trained to do the job he had not followed the rules. He'd let the rig go too fast, and if I remember correctly was lucky not to have been in a major accident.
Many of these old vehicles are fine to drive, empty, but load them up and they require a bit more skill and lots more patience.