[The Q Dr]

Interesting.....I stumbled across your thread looking to see if rear camber is adjustable on the MK2 (2nd gen). I have a similar but opposite problem of too much (negative) camber. I put mine on the lift today. from what I can tell, the rear toe (only) is adjustable, and everything else is fixed. It does look like my upper control arm bushes are a little sloppy/worn. Not surprising after 232k+ miles.
I'll defer to a definitive answer about adjusting the rear camber, I suspect that aftermarket adjustable links would be in order.
As to your issue of extreme positive camber (the way I read your post), I'd suspect previous accident damage, and/or that the ride height has been artificially raised. Can you get it on a lift to see?

 

[Renny1]

Just to clarify, the tyre side furthest inward has a bigger circumference than the tyre side closer to me.

Mine is 90,000 miles. It may have been a deformity. I do not remember hitting a pothole, but who knows? I took it to the tyre shop today and they had some used Michelin Latitude which had the same tread depth as the fronts - so I bought them and put them on the rear. Good because now all 4 are the same, before I had Bridgestone Duelers on the rear.

I inspected the suspension while the wheel was off today at the tyre store with a prybar and could not locate anything odd. I was hoping for some advice on here on what to look for before getting it aligned.

I do remember the rears wearing unevenly the last time I changed tyres, and the fronts being OK. And now, the rears were wearing significantly faster than the fronts which still have 4-5mm of tread. The Duelers were down to 2-3mm. Any idea why?

 

[Buffalo4]

I believe that toe-in on the rears will cause the outer treads to wear first. Have that toe-in checked or look on the Internet how to check it yourself.
Buffalo4