Can anyone tell me about carotidynia as a subset of vasculitis/arteritis in relation to ctd? evidenced by high crp/enlargement of carotid bulb/pain

May not be arteritis: Carotidynia may not necessarily be related to arteritis. The elevated CRP and possibly other lab could suggest arteritis. I would suggest looking for takayasu disease. But this carotid pain can also be due to myofascial noninflammatory.

Inflammation: Carotidynia indicates there is ongoing inflammation of the carotid artery. Active vasculitis/inflammation needs to be treated with a course of steroids.