You expressed and interest in the exhaust and how it was mounted so as I have just fitted it as the final fit towards the test I thought I would post a couple of pictures.
The Rover outlet manifold is modified first to take the entry to the Cat further over towards the wheel side. I have a Lotus S2/MG TF Cat bypass but the Cat, complete with the bend in are very expensive so I have manufactures a custom bend, adaptor pipe to allow the much cheaper Rover Cat to be fitted for the emissions testing.
The rear box is a lightweight Lotus Elise S2 Sports box I got cheap of eBay and is 'cut and shut' modified to mount vertically the other side of my custom rear frame and the outlet pipes nicely curl down to miss the underside of the body. You may notice the custom clam hangers too, I have to relieve a shade out of the underside of the n/s one to get the clearance I needed. You are allowed a 150mm exhaust 'extension beyond the last vertical body piece' before it fails the IVA, I am at 130mm. A small modification to the rear clam ensures this measurement without interpretation by the way.
All that was left to do was hang it firmly and we are up and running... That should be enough rubber mounts to stop is touching anywhere...
Hope that's clear.
The rear under-body skirt (that nobody fits normally)can still be fitted to hide the box hanging below the body line more brackets to be made later....
A little trimming and tweaking (and bending) on the hangers and it should be good to go..
This install works for me it may not work for other's its just another solution for the kit.