AWD shudder/vibration when turning...
 

I’ve had the prop shaft off for ages on the R AWD thinking the angle gear was done for.

Having found another second hand one and had it fitted, along with a second hand viscous coupling, prop shaft reconnected. Unfortunately there is still quite a shudder when turning at low speed, feels like it’s coming from under the car and gets worse the more lock applied. Feeds back through the steering as well a bit.

Did not do it when the prop shaft was off.

Likely culprit? Diff, prop shaft? I’m somewhat at a loss?

First of all, make sure the grease in the prop shaft universal joints hasn't dried out. The ones at each end of the prop. Then make sure there is plenty of gear oil in the angle gear housing. It holds 1 litre. These are simple things to check and cheap to rectify. Otherwise it could be any of the parts concerning the AWD