RANGER. Those are wonderfully delicious squash. I have kept a butternut for 14 mo and eaten it, best keeper I've ever had.
I cut the squash off the vine when they are ripe. Do NOT intentionally break the stem off the squash, they will decay there first. Next I lay them on a rack in the shade for several weeks, that dries and toughens the shell, if really dirty was the dirt off before letting them dry, or cure.
When I'm ready to store them I dunk them in a fairly strong solution of bleach and water, maybe 2 cups in about 4 gal of water. Bleach kills any surface bacteria or unseen mold. After dry I store them in milk crates in as cool a place as I can find.
I'm looking forward to getting my catalogue and tasting the new squash that LONGWINTER posted about. POWDERMAN.