I did this. I took the cladding off, and degreased and scrubbed and rinsed the hell out of it. Then I used spraycan adhesion promoter, before shooting it with primer. Finally I did two spraycoats of the rustoleoum spraycan bedliner. Did the same on the grill and bumpers, and the rear vents.
I also did my tow hitch, and D-rings, but without the adhesion promoter.
It looks great, actually. It has been about 5 months, and it hasn't faded. It sprays off clean. if I had it to do over again, I might use the roll on liner, because it gives a thicker, more textured appearance.
Pics in build thread
Build thread is way out of date, got a lot to add to it, but the cladding is in there for sure.