It sounds like you are on the right track. I'm almost 6', oh well really 5'11.5"; and I rode the 58 cm LHT only twice for a short time. I am building one now in 58cm. I really vacillated about getting the 58 or a 56.
My point is that the 58 felt about at the max. of what I think I'd be comfortable on. It did have a 120mm stem, and I plan on using a 90mm which is close to an inch shorter. The LBS that I rode at left the steerer tube uncut, and it really did not look too bad. If you interpolate all the antedodal information from all our posts, it seems like your choice was a good one. How about letting us know how it turns out!