Fitted Deserts
 

I've just fitted Michelin Deserts to my 84 Tenere and its a tight fit. (they look really good). There are millimeters to spare in the swing arm.
Only had to get a longer break connector rod and put a couple of spacers on the chain gaurd.
Just on question.
I've only got one setting left to move the wheel back and adjust the chain tension once it streches. (Ive got a New DID chain)

My thinking is that by the time the chain streches some of the tyre tread will have worn down and I'll beable to move the tyre forward a bit more and take out a link in the chain to take up the slack.

Does this sound like a viable plan?

I think maybe you can cut down the side knobbles of the tyre to get some more room (is that where it's tight?).

Your chain WILL stretch. But the tyre may wear faster, possibly leaving you with some room, IF you move the wheel asap.

I would cut it down to get yourself some more room, FWIW.