Does anyone here know about Amercian classic cars? The Corvette Stingray in particular.

A bit. Step for a hint, particularly wrt year or at least bodystyle.

Lady E used to sell Yanks for a living. I've not seen her around for what seems like months (guess she's getting lots of work off the golf and cricket).

Thats a good point, I'd forgotten about her!

Looking at a '68 convertible.

As with anything using GRP, check for body crazing. Unless highly tuned, the engine and box are pretty much bullet (or even Bullitt? ) proof but there may be issues with interior condition and chassis rust.

I'm trying to find if its possible to do a conversion to servo assisted brakes - the Corvette forums are a bit slow responding and I'm viewing a car this week.

Probably, but don't ask me how, or how much it will cost!

Well I've now looked at a Charger that has had a servo added, so it is possible and not very expensive either.