I would agree with the Stones River Battlefield visit on Friday afternoon. There are a couple decent gun shops in Murfreesboro, as well, to include Outpost Armory (owned by Chris Barrett of Barrett Firearms fame) and Bullseye Gun & Range (right off I24 at Exit 81, kind of behind Cracker Barrel). there's a great cigar / craft beer bar on the square, called Liquid Smoke. If you're into cigars, you should check out their humidor (which is also the name of their cigar shop next door, with a pass through door between it and Liquid Smoke).
As was said, you'd do well to keep your head on a swivel and not leave valuables in your car overnight.
In Lynchburg, you should eat at either Miss Mary Bobo's if you can get a reservation or Barrelhouse BBQ (try the Grilled Cheese on Crack).
Between Murfreesboro and Lynchburg, you're going to drive right past the Nearest Green Distillery. Nearest Green was the slave who taught Jasper Newton Daniel how to distill whiskey using the Lincoln County Process. The distillery was opened several years ago and they've won quite a number of awards for their whiskey.
If either of you are Squires, mention it when you sign up for your tour at Jack. They'll put a sticker on your tour pass and the tour guide will usually acknowledge you when they welcome you on the tour. The Squire House in front of the Visitor Center is well worth a visit if you are a Squire. even though they're retired, you'll still find Goose Baxter or Randall Fanning hanging around and telling yarns from time to time. Even if they aren't there, Miss Kathy and Will are both worth visiting. (You also get a free gift for visiting.) Even if you aren't a Squire, your tour pass and a minimal purchase will get you a free shot glass at the Lynchburg General Store and a couple other area stores. (Oh, if you are a Squire, they offer a discount, as well.)