I installed the splash guards myself. Not difficult overall. The biggest challenge was getting enough clearance under the car for the drill and drill bit.
There are guide marks at all of the drill points that are easy to find. They’re easier to find if you have a work light handy. There are a few other dimples in the plastic that look like the guide marks, so I recommend matching up the splash guard to verify you have the right spots before drilling. Also, definitely follow the instructions and start with a smaller hole and work your way up to the final size.
It’s not obvious in the instructions, but you only drill the plastic cladding. The drill bit never touches sheetmetal
I used the old bolt + nut trick to pull the jacknuts. Works like a charm and only cost $1.60 USD in parts. If you do this same trick, you’ll need an M5 machine bolt that’s at least 5 cm long. I used a wing nut instead of a hex nut and held it in place with a wrench. Not what I would typically do but I found the wing nut easier to hold in place with available clearance and contour.
Some photos of the finished product (after several rainy days driving). The splash guards are quite subtle, but do seem to reduce road spray area a bit