Sorry, I should have been less general with my first request for info.
Okay, the towbar is a Bosal, purchased from a very large company that sells lots on e-blag. They do show specific wiring looms for some cars, Audi, BMW, Ford, Mercedes, etc, but not for Alfa. I've checked with other tow-bar suppliers in the UK, and none do specific wiring kits for Alfas. Likewise, Witter do not do a specific wiring kit for the Alfa.
Thanks for the note about the bus. I don't understand fully, but I know that many modern cars have trouble with power delivery when not in use. As I've found this little plug bolted to the rear panel, it would be a shame not to utilise it.
All drilled holes have been heavily smeared in grease, as have the bolt threads to aid taking the bar off, if necessary in the future.
The wiring is through to the boot, I squeezed it in the same gromet that takes the number plate light wires, and the PDC wires, so it won't chaffe on the body.
I think I'll pop down to my local dealer tomorrow, and have a look on their microfische.
In fairness about pre-drilled holes, on my old Doblo, not only were the holes in place, but some even had threaded nuts welded to the chassis.
I suppose it's a car more associated with towing.
Next, what will I be towing?
NOT a caravan!
I know that there's a growing band of 'vanners on here, but I'm not one of them. In my quest to deplete the world's fossil fuel stocks, I will be towing my race car, race bikes, or quad around. The main reason for putting a tow bar on the 147 rather than using the old Doblo, is that if the race car fails on noise at track days, then I can take the Alfa round instead.
Yes, it is 'SLOW' in Welsh (I'll explain one day, though it is boring). I used to compete in a lot of bike events in Wales.
Unfortunately it's also Arabic for the world of the living dead, which prompted a couple of questions when I raced in the Middle East, a couple of years ago.