Looks good to me Pete
Here is mine with the inserts machined and glued in place, I used stainless for everything and the pillars can be unscrewed if I ever feel the urge to change the length which is unlikely.
All that is left now is a final light sanding and oiling and drill for the locking screws and add some inserts so the grub screws are neat and flush to the stock. Yes, I used the dog to hold the removable section in place, he watched with about as much interest as you can get from a Labrador half asleep in the sun.