Thanks All for input. Apologies for not responding, didn't seem to get notifications. It's an ex academy car and was upgraded to super sport so not standard. I note the drop link top bolt arrangement is different to the Guide. In the end I took the easy way out and popped into PGM as they are only 20 mins away. The ARB blade was bent inward, presumably some previous trauma. No other obvious indications of cause though. #6 - I'll look into that thanks and as time allows get a full geo done.