Take your time with it. You don't HAVE to roll your odo. Just swap over the odometer from your current gauges.
Follow that how-to, to remove your odometer gauge from the cluster, then do the same thing to the other cluster, and install the "correct"/old odometer to your new cluster. No messing around with accidently breaking your gears(i did that to one).
Basically, take the clear cover off, pop out the speedo panel, carefully take a knife or fork and remove the speedo needle, screw off the three 1/4" screws that hold the odometer in place to the face....do that twice. swap. reinstall.
'01 XLT disguised as a '03 Fx4 Level II
Big. Loud. Slow. Bright.