Looks like they are designed to go into the hole once the stud is removed - the tab won't go behind the swingarm? As in your picture Wooly46...
Removing this pesky threaded insert... Centre punch as close to the middle as possible (there is no danger of running off it you are careful as the steel threaded insert has a large head as you will see later) The thread material is like cheese anyway so drills easily. Took about a minute to drill through to about 10mm deep to clear the arm material. This picture shows where the tang wants to go, but the threaded insert prevents the front of the chain adjuster from seating by about 3mm. I first used a 2.5mm pilot drill to a depth of around 10mm... easy enough to drill in situ without removing the arm. I then used a 4mm and finally a 5mm to gently remove the remaining material... The 5mm drill bit did the trick and the insert popped out The Chain Adjuster then sits flush on the front face... And the tab fits snugly into the hole counterbore... For reference this is what the insert looks like with it's large head that is countersunk into the arm - it's this larger diameter clearance that allows the tang to seat into the hole once removed...
I used thin nuts - half nuts as they are called - maybe the extra years fuses the steel thread into the aluminium deffo worth trying first though!
The bolts sent with the brackets aren’t long enough to allow for this fitment and there is no additional spacer also
You could get longer bolts and space it - but I'm happy with going through the hole, I fitted longer bolts to fit the Gilles lifters. The lifters were threaded which I had to drill out so the bolts tightened. All done... and looking very fine and dandy
