Camper shell question

Are all the camper shells for the 1st-Gen interchangeable? Specifically, I know of one that was on a 2001 x-cab 6.5 bed, and just wanted to make sure it would fit my 2003 (also xCab/6.5 bed). Although I think calling it a 6.5 bed is being generous.

 

Yup it should fit. Only gets weird if you’re between a single cab and extended cab as the rear wall is sloped different

 

Ok. Good to know. Thanks! Also, and sorry for the dumb question, but the camper shells clamp to the bed rails, right? My ‘03 still has its original plastic bedliner which covers over the bed rails. I’m assuming this has to be removed.