It is easier to install the skid plates by driving on 6 inch car ramps and after the car cooled from being driven
You will need 12mm socket on a powertool to remove stock skid plate bolts
You will need 13mm socket to install the longer bolts included. Because of skid plate thickness and stacking of the skid plates, the old bolts will be too short for almost all holes.
Installing
Tighten bolts into the car by hand only, 1/4 or 1/2 way. Repeat for all bolts nearby. Only tighten by power tool when all bolts are in place and tightened lightly
install order:
1) gas tank (by itself)
2) transfer case (bottom layer)
3) transmission
4) engine
1) Gas Tank Skid Plate first
Vehicle front is on the left in this photo
Don't install the 2 brackets which bolt on (on the right in photo)
Support the skid plate 6 inches off the ground on top of a bo
* Align the bolt-on-brackets, insert the skid plate mounting bolts to car, all loose
With all bolts in place, tighten each bolt more
2) Transfer Case
Place 3 bolts as shown into the holes partially by hand
The other side of the skid plate, the tip, needs a bolt and nut and wider washer. Place bolt through the hole, and washer and locking nut on the hidden side. In case the bolt/nut were not included, you need to get a 5/16 or 3/8 inch bolt, 1.5 inches long and a locking nut and 1/2 inch washer.
3) Transmission Skid Plate
Keep the Transfer case skid plate from before loose sill
Insert 2 top and 2 bottom bolts (the shiny ones)
Align all properly then tighten all but the top 2 bolts -- this is the Engine skid plate side where that plate is about to go
4) Engine Skid Plate
The only skid plate I have seen loosen and that's what 2 locking washers are provided for the front facing bolts. That only happened with an older design of that skid plate.
Tighten all 4 bolts by hand, then tighten one bolt more, then another, then all the way in