I'd like to bump this as i have exactly the same question?
(currently converting a uniglide to hyperglide for SS conversion)
you can easily convert the uniglide freeehub to singlespeed without converting it to hyperglide.
all you need to do is to put the cog and spacers ( or the ss conv kit) on it and then tighten all that together by screwing an old bb lockring on thee threads at the end of the freehub body . just where the last small cog of the uniglide cassette was screwed on originally.
you can easily convert the uniglide freeehub to singlespeed without converting it to hyperglide.
all you need to do is to put the cog and spacers ( or the ss conv kit) on it and then tighten all that together by screwing an old bb lockring on thee threads at the end of the freehub body . just where the last small cog of the uniglide cassette was screwed on originally.