I re-mounted the original knobbies, and rode the Big Beast there. Since I had all day, I eschewed the Interstate for the back roads (well, as much as there are on the way to Big Bend).
Here's the route I took:
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I left at 8:30 in the morning, arriving in the Chisos Basin for an early dinner at about 5:00 p.m.
Lee and Tom left San Antonio around 3:00, and via I-10 arrived in Terlingua around 9:30 pm.