Previous lockring was cheese. LBS hadn't a clue why it got so stuck. Tightened the new one in place and went to the shops today on the hubs and I'm happy with the ratio I've got. Threads look pretty good to the eye so I'm just going to hope it works if I ever need to change the sprocket.
Any chance that’s why you couldn’t get the previous lockring off? No comments from LBS on the threads, etc?