Thanks for the ideas!
We have come quite a way since I posted this thread. I agree, MB dealers in general have not the faintest idea what a Marco Polo looks like or contains and are hopeless at thinking outside their own box. But MB Exeter, when we finally got to the correct part of the concern, are an exception. Though they had no possibility to help in our time frame they passed us on to Car Body Shop Exeter, who found time to see us the same day we called and were both competent and efficient. The problem was unfortunately the compressor, which can't be replaced without taking the whole unit out of the van. Given that we thought it would be better to replace the entire 20 year old unit. The RC1142 is of course no longer available, so that means finding a fridge box that will go in the hole with appropriate fitting skills. Exeter Car Body promised they could and would do that in less than a day if we could find a fridge.
A useful item for others in our situation ... the place to get these fridge boxes is marine suppliers, because they are mostly used in small boats. There are three potential models, in all cases the "guts" can be mounted separately from the box, making it easier to fit in an existing hole. There are several such suppliers, the most helpful and competent was S G Home and Leisure, who went to the trouble of phoning Dometic to verify what I was beginning to suspect, that there was a very long lead time on the unit I was proposing to order.
Long story short, we've given up before we return to Norway (lots of small boat suppliers there!).
The models I have found that should fit are
* Vitrifrigo TL43R
* Dometic CB40W
* Isotherm BI 41
In my current order of preference. I'll post an update when I have one in and installed.
PS these are all self contained and will not talk to the MP central control unit. That will just think the fridge is off.
