Thank you for thinking so highly of us! We love to hear positive feedback from our customers!
You are correct in thinking that upgrading from 3.55 to 3.73 won't give you as much of an impact as you're after. You will definitely notice the get up and go of upgrading to the 4.10's over your stock 3.55s though! I would suggest sticking with the 4.10's; anything steeper and you would really start to see the effects on your gas mileage, etc.. Even if you were to start doing more highway driving with the 4.10's installed, you would not notice much of a decrease in mpg, which is always a good thing!
In regards to the installation and bearing kit, I HIGHLY recommend you replace those as well. Cars with over 30,000 miles have bearings that are worn to the gears. Replacing all the worn out bearings, shims, etc... when installing new gears will prolong the life of your gears and will prevent any future problems. If a bearing goes bad down the road, you may end up having to replace the bearing and whatever else that bad bearing damaged as well. It's a great preventative measure for a potential giant headache.
Changing your gears will also cause your speedometer to read incorrectly. If your have an automatic, it could also cause your shift points to be incorrect as well. Best way to correct that issue is to get a new custom tune for the car. If you have a tuner with AM/Bama, you have Free Tunes for Life and can just get the tune updated for the new gears. If you don't have a tuner, we do offer a kit that includes the gears, a handheld tuner, the rear end installation and bearing kit as well as the necessary gear oil to complete the job!
I have attached the kit below if you'd like to take a look! I completely understand that $179.99 for gears along seems like the easier way to go about this upgrade, but if you want to do the job the best and most efficient way the first time around, I couldn't recommend the gear combo kit more!
Any other questions, please give us a call! We'd be glad to help!