Just going through my boxes of bits I have yest to fit to the chassis, and I literally tripped over the roll bar, so thought I'd take a look at it, as to where/how its fixed to the car.
The fixing looks very simple, just a large M12'ish size bolt in the end of the roll bar, which I assume you need to drill a new pair of holes in the small square plate on the back of the car then then screw up through.
Now I have seen pretty much everybody fit the bar once the body is on the chassis, which I understand as you need to drill through the fiberglass, and then into the steel chassis below, but is there any reason not the drill the mounting hole now, and then when the body is fitted be able to drill up through the fiberglass from underneath?