It's SAE lead screw. Not very helpful for all the Japanese bikes I work on! Threading is not my priority though (which seems odd in this community), so it's fine. My buddy has the metric lead screw on his - he bought it as a replacement, so I am assuming that I could do the same when/if the time comes.
I will definitely have to get that cover going when I do the shims. Sounds like a good preventative mod.
Got the QCTP from LMS in preparation for the lathe's arrival. I was a little disappointed to find the allen size for the tool holder set screws is standard, although the large bolt on top to secure the main post to the slide is metric??? I thought I was going crazy - and would have stripped the things, if I hadn't stopped myself and tied a standard wrench. I literally have 10 metric sets floating around the shop (and countless singles), and only 1 incomplete set of standard sizes. Happened to have the right one, thankfully (7/32 or some such).