Don't waste your time regearing to 4.10's, honestly.
My 05 sport trac came stock with 4.10's and 255's. I'm running 33's now on the 4.10's, and it's okay for the most part, but I definitely wouldn't spend money to regear unless I went with 4.56 atleast. If you look at a gear calculator, going from stock tires with 4.10 gears to 33" tires with 4.56 brings you back to stock, or very close.
And 4.10's with stock tires was great. Definitely not too low, it was just right in my opinion. Remember that the SOHC engine needs higher revs to make HP, and is happier at high rpms.