Apparently mud guards were an optional extra ta the time my Pathfinder was new so I decided to get an OEM set from Watford Nissan.
All 4 look a little like this
The front ones are extremely easy, simply remove the 3 screws on the inside and 1 under the wheel arch, (and discard) place the guard up against the arch and replace the screws with the longer ones included in the pack:
The rear ones filled me with a little more trepidation as the instructions call for a 9.5mm and 6mm drill bit but having looked at it it's still nice and easy.
(I didn't but removing the wheel would make it much easier for access)
The 6mm holes are pre marked and just require some careful drilling.
Then slot the clips over the hole to provide purchase for the screws.
The 9.5mm bit is used to round off a square hole under the wheel arch, which should contain a plastic retainer (mine were missing anyway!) to be discarded.
Hole drilled square:
Then same as before present the guard to the arch and screw in the 3 screws
In the pack is a round plastic lug nut which goes through the guard and into the hole you just drilled square.
End result:
FRONT:
REAR:
All 4 look a little like this

The front ones are extremely easy, simply remove the 3 screws on the inside and 1 under the wheel arch, (and discard) place the guard up against the arch and replace the screws with the longer ones included in the pack:
The rear ones filled me with a little more trepidation as the instructions call for a 9.5mm and 6mm drill bit but having looked at it it's still nice and easy.
(I didn't but removing the wheel would make it much easier for access)
The 6mm holes are pre marked and just require some careful drilling.

Then slot the clips over the hole to provide purchase for the screws.

The 9.5mm bit is used to round off a square hole under the wheel arch, which should contain a plastic retainer (mine were missing anyway!) to be discarded.
Hole drilled square:

Then same as before present the guard to the arch and screw in the 3 screws
In the pack is a round plastic lug nut which goes through the guard and into the hole you just drilled square.
End result:
FRONT:

REAR:
