Thank you all for the replying to this post.
I do indeed have a placard on the dash. It says 6.8 gear ratio.
I am fairly sure that the rear end gears have been changed. The only way that I will know is to do the spin the tire and driveshaft method of calculating.
My computer died but magically came to life again after two days. Weird. I sure hope it continues to work. I love coming to this site. Gonna go look at the tranny today. Hopefully I will find the tag with the data on it.