Input speed sensor 2001 Sante Fe

That's actually the output of the vehicle speed sensor.
The input of the speed sensor is actually on the right front wheel assembly. It's the little electrical knob looking thing right behind the control arm.

Fairly easy. You have to remove the breather hose and the two bolts that attach the shift linkage on top of the tranny. Unplug the wire lead & one bolt that holds it in. You will have to twist it as you pull it out.