The two front fasteners are fairly easy to get to, but the rear two are a nuisance. Givi provides loose nuts and bolts and the nuts are deformed to make them self locking, so you need a wrench to hold them all the way on and off. The rear two are barely visible so keeping a wrench on them is awkward. After a year of fiddling with loose parts I finally welded the nuts in place to the brackets and now just turn the bolts in, much easier. The provided hardware takes 13 mm wrenches which aren't used anywhere else on the bike.
With my mods it takes 5 minutes or so to install the skid plate.