It not bad. Under the truck and to the trans is easy. The hard part is twisting yourself under the dash and getting that stiff cable around the column and in.
You will need to take the knee bolster down and then the stamped steel plate on the bottom of the column. Then it all comes out pretty starighforward like. You don't need to remove the seat or much trim to get to the cable under the drivers floor carpet. Like i said, under the truck is cake to do.
Adjust the new cable after install. The springs are suppose to provide the tension enough to take out cable play. Let the two pieces slide together back and forth at the adjustment and then let the springs do the setting. Then snap the white plastic retainer in place and check for proper movement at the dash shifter.