What if you made your bracket threaded (fasten a nut to the bracket?) and forgo the t-nut? Also, move your ‘lock nut’ to the bottom side as well.
Then, you can turn the big handle below the bracket to adjust height, and tighten the locknut from below as well.
I found that the Bosch table top router table’s table fit between the fence rails of my Shop Fox saw…. It’s made out fo aluminum and has worked out quite well. I owned the router table before I bought this saw, and it was just a happy accident that they were the same size (at least, I think it was).

-- John F. SoCal transplant, chewer uppper of good wood