What do need to take apart to replace the top of t
For starters, you are going to have to remove the steering column from the truck, there is no way you can perform this task without removing the column. After the column is out, you will need to remove the light switch rod, then you will need a steering wheel puller to remove the wheel.
Now loosen the clamp that holds the upper steering housing to the steering box so you can remove the upper steering housing. You will then need to drive out the pins that hold the spark and gas rod levers to the rods so the rods can be removed. Now you can drive the old upper bushing out of the column from the bottom. Those parts are a die cast and normally they swell and are tight in the hole. To install, repeat the same process in reverse.