So here is my version of @samuel313
's skid plate. I've only messed with the transfer case skid so far. Various reasons. My plan is to use 1/4" 6061.
I wanted something supported on both ends. The cross member by the gas tank is pretty obvious, and now that I crawled out from under my rock... I see that pretty much all the usual suspects you could buy skids from do it that way too.
Started by laying out some cardboard using the plan from @samuel313
. Added an extra 12" on the end but it wasn't quite enough. You might see the chunk I taped on the end of my cardboard skid. Maybe my cross member is different or maybe I still can't do basic math but either way the bolts didn't line up. A few tick marks and measurements later I got that sorted out. My hole pattern is in the files if you are curious, but if you are going to go make your own I'm sure you'll figure it out.
I changed the angle from 8 degrees to something like 9.2 degrees. This is just a 1" offset at whatever distance it is. It gives maybe 1/8" more clearance below the transfer case than Sammy's plan. Partly because I expect it to flex a bit being aluminum, and partly because I'd rather err on the side that still works. I also swapped out the 15 degree up bend with a flat, bend, flat sorta arrangement. This is just to give that 1" clearance for a length of 3" about where the lowest part of the T-Case is. Oh, and it needs a couple of drain holes drilled randomly by hand but aren't in the model.
The side rails are 2" tall in the center and taper. There is a pic in the ZIP showing how close it gets the the exhaust pipe on the passenger side. But it shows an early version before I adjusted the angles and tapers. I fully expect it to fit. Then I fully expect to notch it out a bit when it doesn't really fit.
The ZIP file has solidworks, IGS, DXF flat patterns, and a couple jpg files. Solidworks thinks it'll weigh 12lbs as shown.
And since I don't have any shop access for now it might be a while before I get to build a real one. I get really frustrated trying to make nice dimensioned PDF files. I'm working on it. Old dog, new trick...
I seem to forget everything I learned since last time.
I usually post my design files as simple public domain, but this is based off his work which says Creative Commons. So, I guess, this can't be public domain. I don't know.
EDIT: (swapping attached images into the project album)