Hi ValleNorte,
I hope you see this in time to direct your Dealer, but under no circumstances let them weld the system.
We spent a lot of time working on this conversion and I will try to explain the basics so that you can have an informed conversation with the Dealer.
Firstly, they need to follow the fitting instructions to the letter, these are very comprehensive and should be easy to follow. The conversion is mounted to the rear of the body, just below the rear crash bar, this is a critical piece of information, as it means that the conversion itself is held rigid, where as the original exhaust system is mounted on rubber hangers, which allow some slight movement. If they weld the pipes, they will restrict the movement of the standard exhaust and introduce noise and vibration to the full system including the conversion, and could result in a fatigue fracture.
This is where the use of the heat wrap comes in. It is actually performing two functions, firstly it reduces the heat transfer between the standard system and the conversion, and it also acts as a buffer to ensure that there is no noise as a result of the standard systems movement against the fixed conversion. The section of heat wrap on the centre transfer pipe is there to ensure no heat soak issues near the reverse / rear fog lamp unit.
Again, I cannot stress enough that they need to fit the conversion exactly as per the instructions to avoid any potential issues later.
If you have any questions regarding the fitting instructions, please don't hesitate to ask me. I will be happy to do what I can to help.
Best regards,
Richard.