front sprocket showing shiny wear shine on left side

[PaulSmith]

Changed front sprocket back to stock 16T plus new DID chain 2000kms ago but today when rolling to a stop to park killing the engine noticed louder than normal chain noise.
When I changed over to the new I adjusted chain tension using a vernier calliper for alignment which did not result in exact swing arm notch alignment. I have read before that this is a better method over relying on the factory marked alignment marks.
So today I adjusted chain tension using the swing arm alignment marks as it had been issue free before with regards to front sprocket L side wear.
Is this a known for the Gen 1 Thou I wonder?
ie  vernier or swing arm marks for wheel alignment?

I dont quite understand your method. What are you measuring with the calipers?

My approach is to make sure the chain can barely touch the underside of the swing arm with the marks roughly lined up, partially tighten the wheel, just enough to take up the tension, set the right mark to match the left, check the chain still barely touches the underside, tighten the wheel half way, check the marks, check the chain no longer touches, adjust if necessary, then tighten fully.