Cool build Lofty. What's the travel/opening of the vise? Unfortunatelly I could probably buy 10 Fe$tool items for the cost of that hardware here in Australia. Just browsing the internet for one saved me the purchase for the 'peckers tool.
The "mm" is a neat finish. Have you considered making a routing template for it? FAIW, distance inhibits, but a local laser service could make a perfect/smooth template.
I may change the material down the road. Not fond of the dark streaks after the finish.
You'll need a good parting tool for that exercise.
If your first cut is too short... Take the second cut from the longer end... LBD