Once we'd got the rolling shell to my brothers (Uncle Spike!), we were able to get on with the roll cage.
We made the roll cage mounting plates out of three millimeter mild steel. We used cds pipe of the relevant rating to make the main hoop. This took a couple of attempts in fairness!
The roll cage was built to the relevant regs in the Blue book.
We added in more structural bars than required by the blue book. It seemed sensible to sacrifice weight at this point for safety.
We spent the time to get the seat mounted in properly too. We had to trim some of the 'tunnel' to move the seat inwards. The angles of the car made the seat protrude out of the side.
We also took the time to use a Corsa C steering collumn. This we mounted onto the main rollcage.