Here's a close up of the original bracket.
The bracket is attached at the engine block end with a 13mm hex bolt; the alternator end with a 15mm nut on a long bolt through the alternator body.
Remove the 13mm bolt and the 15mm nut. Remove the oem bracket.
In theory you simply need to adjust the new item to the same length as the original and refit using the bolt and nut.
There is a small issue, however, in that the new rose joint ends are substantially thicker than the oem bracket. On the engine block end, the usable threads are reduced by about 50% (about 10-15mm) so you
could reuse the bolt. I sourced a longer bolt to restore the lost threads
Here you can see a comparison of the different thicknesses.
On the alternator end, there is not sufficient bolt length to fit the rose joint and the nut. You will need to source a longer bolt to fit this product. Again I found a longer bolt
Here is the new adjuster in place.
Adjusting the alternator belt is now much easier!