I've got 35" tires on my truck. Originally, I had a TH700 trans with the great overdrive, and I put 4.56 gears in (replaced the factory 3.73's). Now I have a TH400, so I'm spinning over 3K RPM on the interstate with no overdrive. The gears are great for everything except cruising, but it really sucks for that. Should I go back to 3.73, or maybe split the difference with 4.11's? What RPM does a stock 350 like to cruise at anyway? BTW, since a gear swap is out of my league, what would a typical shop charge for labor? Thanks for any advice!