This is great. We talked over email about this subject about a year and a half ago. At that time, you were still unsure if you wanted to try and I am so glad you did. I have recently become very compelled to try this as well in my growing interest in Guadalupe Mountains National Park. The park itself is not very developed. No busses or any roads that go through. Just three entrances that basically serve as “ways to get on the trails”. Because most of the park can only be seen by backpacking in. There are two car accessible campgrounds and almost ten backcountry campgrounds. So really, this park can only be experienced in the backcountry. The reward is an beautiful and empty landscape. Like you, I shoot Large Format but luckily only 4×5, which should make the task a whole lot easier. All I have to pack is my camera, pentax spot meter and film holders. It should be doable. I got a 60 liter Gregory pack but I havent tried packing it yet. I am still unsure of how to protect my 4×5 equipment. My only idea at the moment is plastic bags and t-shirts. Any suggestions?