There is so little difference between 3.55 and 3.21 I wouldn't even bother switching them.
I think running 14 inch tires will feel like you have 3.55's anyway.
You really can't go wrong no matter which gears you use.
Based on how my Dakota drives with 3.55’s and 2.35-75x 15 tires, I find that even on some small size hills, the trans drops out of LU and OD pretty easy. I’m a bit concerned that with 3.23s and 14 in tires it’ll be all the time.
