Removing longbed fleetside bedsides?

[Delo93]

This is my first post on this forum... i'll save the intro for another thread. Anyways, i'm wanting to swap bedsides from a rust free bed i have. How do you remove the bedsides? I can see the front part just unbolts, but not sure about the rest. I would swap the whole bed, but the cross rails and front panel are in much better shape on the bed that is on the truck now. I also want to strip the bedsides down and prime them properly before reinstalling. Thanks for your help in advance and i'll post some pics in the next couple days.