Here's a link to a (long) detailed write up on the fitting of air/con to a series one BX16V.
The things we learnt along the way can be used as a guide to anyone retro fitting air/con to any make or model as a lot of the traps are universal.
It should be remembered also, that by trade I am a refrigeration and air conditioning mechanic with many years experience (albeit not all that much in car air/con) so I am aware of a lot of traps that the layman wouldn't find until it was too late and my sone, who owned the car and did most of the electrical and donkey work is involved in automotive electronics as a part time business.
I point this out so the reader is aware that whilst we aren't just the average DIYers as regards this type of work, most of it was in unchartered water for us, so the lessons learnt can be used by others.
It's not a simple job; far from it, but again, not an impossible one either.
The full story is here:-
http://www.frenchcarforum.co.uk/forum/v ... hp?t=11605
Alan S
[edit] Updated link
Retro fitting air/con
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