I don't know the car but it seems it had a rather large shunt to justify a rebuild at 3 years old, it could well mean that it has been put back together in a very good way I wouldn't be too worried about that, Techniques are an established good reputation company.
I would be more concerned about whether the original seats and interior were with the car otherwise it will only be useful as a race car. The one's I have seen are bare aluminium including the door cards. I rather think the Lightweight designation means stripped out.
We have a couple of racers on here that maybe know the car ?
The Roadster Lightweights never had any interior trim, they were designed as racecars from the outset. They don't make very nice roadcars without substantial work.
I was heavily involved in the first couple of dozen built, and even finished building a few for the factory.
Simon @ SiFab.co.uk