the speedo gear is attached to the end of the vss (vehicle speed sensor) which is on the drivers side of the transmisson, behind the reverse light switch.
in the transmission, looking at it from the tail, should be on the left side kinda towards the back, actually a sensor, two bolts pops it out, then a c-clip holds the gear in place..if I remeber right...
good luck
Depending on how drastic of a change you went with the gears (4.10's and up) you have to change the gear that is around the tailshaft as well (inside the tranny)
Depending on how drastic of a change you went with the gears (4.10's and up) you have to change the gear that is around the tailshaft as well (inside the tranny)