Ok update.
Exhaust and crossover is not fitted as yet
I am going to see Neville tomorrow to see the problem for myself, then I will get in contact with Trevor at CES to see what can be sorted out.
From what Neville has told me, each of the 2 parts fit perfectly on their own, but when you try and match them up the crossover does not match up with the mounting points (sitting much further back than it should), which then brings it to within about 10mm of the rear wheel.
Given the $$$$ involved I want to see what is going on before Neville does any cutting of pipes etc, and frankly I expected it all to go together with no problem at all given the excellent feedback that has been given on the CES product.
So pretty much highly pi++ed off at the moment...............