Originally Posted by JK_44
This is the setup I used in my truck (Tacoma) and it has worked very well over the years.
This guy's website is a great resource:
I based mine on that one too, though for a Dodge Ram 6' bed. I've liked it a lot, though I should have made the door up front a bit wider to allow getting into the side pocket. The 2 major changes I made was rather than dividing it into 2 equal sized compartments, I did a 2/3 wide and 1/3 wide, and I added an extra access door at the back.
The 2/3 side has it's top (sleeping surface) fixed permanently to it. The 1/3 side has heavy duty velcro holding it down. It is sized so that I can remove the top piece and put my bike in a fork mount holder. I reverse the handle bars and then put in an additional piece of wood (~2' deep) near the tail gate which allows me to sleep in the bed with the bike in the truck. This fills in part of the gap from the missing decking. Without that I wouldn't fit as I barely fit diagonally anyways.
The other change was rather than just having the access door in the front of the bed (near the cab as the web page shows, I made a second one at the rear of the bed that lines up with the tail gate allowing storage of coolers and the like that are taller than the bed. I also didn't bother with the locking setup, the back is open ended on mine.
For interior lighting I find the LED battery lights for closets work great. slap some velcro on the back of them and they stick nicely to the ceiling of the shell if you've got carpet in there.
Definitely expect condensation and frost for winter camping. I keep toying with a portable heater but always get too paranoid on CO poisoning.