camchain tensioners, again!

[Bob Goding]

Due to a financial disaster [I'm sure I'm not the only one!]I may be forced to dispose of the 911[my retirement project]

But I have another engine 2.7 and have been overhauling as the finances permit.
Looking at the tensioners and idlers,this engine has[had] 930.105.501.02 p.n tensioners wth original narrow idlers--with 10mm thick alloy spacers. see Wayne's book pic 7-15
I have a carrera tensioner kit.
With either tensioner mounted ,the gap available for the idler/spacer measures
40 mm[see photo]
The width of the idler including spacer is 37mm leaving 2mm axial movement to permit alignment of the idler sprockets ,I presume.
I have read pos.and neg. about which tensioner to use and havnt made my mind up yet ,but either way I would like to instal a modified idler similar to to Henry's supertec mod with a bronze insert. By sizing the Supertec photos,it seems that the spacer is indeed 10 mm and the overall width is 37mm.
Could someone please measure a later Porsche idler arm p.n930.105.509.00/930.105.510.00[see Wayne's book pic 4-7] and confirm this dimension for me.
I certainly dont wish to buy new items and it is a bit impractical for me to exchange
with supertec as freight both ways will kill it.
Hope this all makes sense!--Thanks