I agree, and BTW welcome to the forum.
Originally Posted by asteffes
You can see from my sig that two of our vehicles are full-size trucks, albeit both are 4WD, and from the photo it looks as though your Sierra is 2WD.
Not to worry, we drove our '60 Ford longbed 2WD all over Baja in mid-sixties and though I stuck us a couple of times in sand (Baja) and mud (Wyoming) we had recovery gear aboard and extricated ourselves each time it happened.
You'll find that there are limitations to every vehicle, no matter how tricked out we make them.
Follow the advice from bootzilla and asteffes. Make the truck mechanically sound and then maybe add a cap to the bed. If you can afford a shell that has windows that open upwards (in addition to sliding screens) you'll enjoy the extra side access these offer. BajaTaco has this type on his 'Yota and we do also on the '04 F-250. I like being able to load and unload from the side.
You should be able to find a used one that you can modify if it's not to your specs. I would suggest, however, that the one you acquire have a strong roof so that you can carry gear on top if you want.
Have fun with your project.
"I'm ahead of the game and can afford to take chances." --Theodore Roosevelt
'11 Mini Cooper Clubman, '04 Dodge Dakota 4X4