I can answer you later, in this week. Let me find some info about this!
It would be great if you would post some information about your installation.
I saw the tread that you have written while doing the upgrade, but unfortunately pictures can't be displayed any longer.
Have you used original parts from Citroen or maybe used aftermarket Webasto set dedicated to C5 ?
I would prefer to use Citroen original parts to have everything fitting properly - mountings, pipes, etc.
The biggest problem the I have at the moment is do I really need to use original Citroen Telestart. It is extremely expansive. It would be far cheaper to buy a Telestart directly from Webasto, but at least from what I see on the electric diagrams pinout connections do not entirely fit well.