So, today, a friend and I (thankfully he works as an electrician for SAS) removed the back panel of the left hand rear cluster and popped the plug out, the earth was very bearded so a couple of minutes with some sand paper and then a go at the inside of the plug with a "de-burring" tool (I am sure you get the picture) and then a spray of contacts spray, put it all back together....... Perfect.... So, a happy ending :bgrin2:
Modding a Volvo, by the way, is like putting make-up of a pig :_poke: