I'm not a fan of landies
All of a sudden I'm going off of you.. But it's ok, Brian will be your new best mate!

Is it a good idea to lose the flexi pipe on the exhaust? I thought it was there so the cab (and attached stack) can move independently of the chassis. Mogs are designed to flex so I'm thinking something attached to the cab and the chassis without the means for some amount of movement will break something? Probably the exhaust?
You've only got to watch one with a large back body driving off road to see how much they do twist. It's pretty incredible.