I'm going to share the docs of what I fab for the mini stock prerunner I'm building now (96 Ranger 4.0) . I've been working in open hardware for the last six years or so and have a small batch manufacturing operation that's been selling some of the parts (we've made parts and kits for over 10k machines in the last 5 years). With the maker movement and hardware tech startups open hardware has a lot of traction right now. I don't know if off road or even motorsport in general are going to be interested in any great numbers. A couple of months ago I joined a open race scale project that is wireless scale pads with a phone/tablet app. There is interest but still only two of us are actively working on the project. The software is in alpha, the electronics are pretty well in process (I've got it operational on a Raspberry Pi) and the design of the phone/tablet app is starting as well as the wireless connectivity.
GitHub - RoaddogLabs/open-race-scale: Open Source Racecar Scale
On my truck project I've just started the design of engine mounts and will move to the shackle hangers and mounts. I've got a older (maybe one of the original) Camburg 4" kits on the front so that should tide me over for a while. Over the next year or two it will evolve into a street legal/race legal truck. Once I get the geometry for the mounts worked out the files will go up on Github and the rest will follow. I'll be sharing everything I make.
I'd expect some pushback here from those that don't quite understand how open hardware works. The arguments will be insurance, liability, lack of design knowledge and perceived quality of parts. Suspension geometry is difficult but doing an open source suspension (or cage or whatever) is going to enable the sharing of knowledge and in the long run make for better DIY projects. There is a lot of knowledge out there and it's not confined to those that do it full time as their primary source of income. This is the fourth car I've built for me though I've built or worked on the builds of about a dozen more. That's nothing compared to the pros but for a guy with a small fab shop in his garage it's a solid starting point. The best way to get something like this going is to start sharing what you have and let it grow organically.