"How Few Remain": that's the novel I assumed was the sequel to "Guns..." Thanks for the clairification and brief review. Looking at my "Few.." paperback I now see I never finished it! I may have to re-add this to my read list.
Re Civil War and time travel, etc, another book along the same vein and on my top 10 list is "The Lincoln Hunters" by Wilson Tucker. One of the few books I'd love to see made into a movie.
I found an excerpt from HFR, I am enjoying it quite a bit.
http://www.sfsite.com/~silverag/howfewremain.html
I'll give that "Lincoln Hunters" book a shot. Sounds interesting.
Either of y'all read Clive Cussler's "Sahara?" Interesting Civil War subtext...if a bit farfetched.