3.91 gears for shorter 60 mph trips

Well 27" and 3.91's are going to run close to 3K at 60, which for me would get pretty old pretty fast

I currently run a 28.3" tire with 3.7x Ford gear, and that's still a tad over 3K at 70. I would not want much higher RPM on the highway

Your gear, 27" and 3.91, from here:

http://www.wallaceracing.com/gear-speed.php