Little insight on the gears, because when I was looking I got all kinds of answers.
I run 37's and did with the 373's for a year, truck was a dog but it did get down the road. Highway actually ran ok, as long as there was no hill and no one got in your way. @70mph my rpm were like 1400 because I have a overdrive trans and 5.7. Running with the 373's can be done but you will cook the trans its just a matter of time. I cooked my 3/4 clutch pack.
Moved up to 4.88's now and a new trans, truck runs good and has the low end power for normal driving. On the highway now at 70mph she's hitting like 1800-2000 rpm's. I talk about this because I really wanted 5.13's and was worried about high speed driving...in hindsight I wish I did the 5.13's.
Now 4.88's will work all day, and most will say that they are perfect. They are...for normal stay in the right lane driving, but if you are a little heavy footed and don't care as much about gas then go with the 5.13 you will have all the power you want and never want more.
Next year I will be moving to the 5.13 because I want power and towing and never want to think about it, or have to put my foot in it to get it moving.