Your picture shows a jam nut, not shims. With that set-up, thread on the jam nut, thread on the muzzle device and clock it where you want it. Then back out the jam nut till it snugs up tight to the muzzle device. Easiest way to get it done in my opinion. I'm not sure I am understanding where you are having the problem, no shims should be required with the setup I see. No offense intended, I may be mis-understanding the problem.
Jim
I see the half shim between the hider and the nut. Had the same issue with my first thread job at TSE way back and put a shim for alignment of the A2 birdcage. Overall I’d say he’s ok and makes the T97 shorter and more attractive I think. That Chinese flash hider looks very socialist if you ask me.