930 chain tensioner install question

Motor assembly continues. (1967 911). I bought/installed the updated idler arms, that are wider on the pivot than the originals. Accordingly, my understanding is that no 'spacers' are required when using the (narrower) 930 tensioners. But I notice 3mmm space between tensioner and idler arm. In other words, the idler arm has 3mm of axial travel. Doesn't seem right, or is it?? Thanks

That is normal

I'm facing with the same situation.
So it's normal but strange : it's for sprocket auto-alignement purpose?

So why adding spacer with the pre-930 idler arm?

You want to let all the bits find their happy places.