For my upcoming Minnesota trip I will try to verify whether 639 is posted at MD 51 and also if this means MD 61 is now posted too.
I drove both routes yesterday. 639 not signed from MD 51 WB (don't know about EB). Also, I drove MD 61 in both directions, and it's still unsigned.
MD 639 signage is weak enough is that the best guide may be to follow the blue H signs, to the hospital that's about halfway on MD 639.
