I've never done it, so I can't speak from experience, but it should be doable as long as you aren't afraid of drilling a few holes. You would need to get a topper that sits flat on the bedsides. Some toppers straddle the bedside rail. If you were willing to trim the fiberglass, that style would probably work too. You would end up with a big gap between the tailgate and the rear glass, but with a little effort, you should be able to solve that problem too.