You'd think (probably not) that builder would address getting into and out of a cab over bed, especially for the older set (like my wife and I.
I cheaped out and bought a Topline aluminum bunk ladder. I looked at wooden ones and even considered building one (with my limited woodworking skills, probably would have been not too cool) so I bought a pre built one.
I like the Topline ladder because it locks into 2 moulded hard plastic hinge affairs that screw to the bulkhead on the bed rail and it locks in so it cannot slide out and let you fall on your kester in the middle of the night for those midnight whiz trips we oldsters always have to make.
very secure but removes in a flash and stores on the bed so it takes up no precious room, always a premium in a truck camper.
My wife and I like it and it works well.... and it's very lightweight too.