I actually didn't make any comment - positive or negative - about the LighTech adjusters, I was simply asking why were you looking to replace the stock ones as they seem to work quite well. And since it's you who is coming here for help - just a week ago you asked for the Service Manual and
I gave you the link - you might want to reconsider your attitude... even if you don't get the answer you want, remember that we're all trying to help when we can, how we can, in our free time.
Anyways, back to the main subject:
LighTech chain adjusters don't seem to be available for the 899. I do not have direct experience with them (so I'm giving you a personal opinion) but even if you find a model that fits precisely on the swingarm, I doubt you would be able to make it work because on the 899 the rear axle is threaded into the right-side adjuster block (see photo I posted above).