Your router table/bench/table saw/router table is taking a such a unique configuration. The way you've had to twist your thoughts and ideas on what would or wouldn't work in your dungeon keep bringing me back to your posts to check out your latest solutions.
I have a suggestion for your router fence mounting board. Make the board wide enough to reach the miter gauge slot and glue a tight fitting runner to the bottom of it. This should make for a repeatable mounting alignment index. Now if you plan on using the table saw at the same time it might be to close for comfort though.
Whittier, CA, USA
Dona nobis pacem