[Ismar1984]

thanks for the input Peter, you're right the tunnel will have to sit pretty high but i am not too fussed with that as i only plan on having two seats in the back.
For the rails i am using 100x50mm RHS so that should help a little with the exhaust going through, I also plan on doing an oval exhaust so as to minimise the amount of material taken out in one direction.

I'll give you a call later in the week, I am in Rosanna so not very far from you.

Thanks,

Ismar