I screwed the X-track into the aluminum/wood wall studs where I could, and leveraged the happy jack mounts by adding 1/8" plate steel extensions underneath the jack track.
Here are the screws I used for the X-track (and cabinet) installations.
This is the upper gear cabinet. Another poster here on the forum gave me the idea of using the horizontal steel straps to create better mounting locations than just using the interior wall studs.
Then I modified the upper happy jack bunk to use as a storage area. I installed screw eyes around the perimeter and used a truck bed cargo bungee net to secure whatever I want to put up there. Most of the time, it has folding chairs, spare carpet, and maybe a small mattress.
Bottle Jack
Today, 03:37 AM in Frame