Let's hear your tips and tricks for prepping inside of K5 for bedliner. Getting all dust out will be fun in the end I know!
That's the same thing I did to prep my bed for herculiner.
I used a palm sander with some 40 grit anywhere I could. Red scuff pad all over after that. Shop vac'd it about a half dozen times. Wipe down with Xylene which is a very strong solvent and is also used to thin the bedliner to get the right spray texture. I used Liner Xtreeme with great results as have a few other on here. This stuff: http://www.sprayonbedliners.info/home.html