No, leave the uisel alone, as it'll regenerate if you delete it, and it won't be happy if it can't find those aircraft mentioned. It's easier to do this -
It doesn't matter what aircraft it actually is as long as the folder name, sim name and model name identify it as, say, bf_109g_6. So you take a Bf 110G that you want in-game, and rename all its parts to bf_109g_6, leaving only the short name in the xdp file reading Bf110G-2, or whatever it actually is. In game, that's what you'll see, although the game engine will accept that it's the stock Bf109g-6.