Congratulations. The only thing I can offer is to leave more than just enough room for the ejected round tray. I don't use one. I eject my rounds into a .50 cal ammo can. It really looks like you have everything you need. The only thing might be the strong mounts, but that depends on how high your bench is. The strong mounts can be a back saver. My bench top is 33" off of the floor and I couldn't imagine loading without the strong mounts. I'm only 5'2" tall and I'd have to stoop to drop the handle all the way without them.
The last thing is if you didn't get the roller handle, get one. I know it's stupid expensive, but it makes a big difference on the long loading sessions. A lot less fatigue with the roller. Other than that, get yourself a spare parts kit, in case you drop a spring or clip. I've had my machine for over 20 years and have only had to replace parts that I lost, not because they broke.