And here it is, along with the lost shot of the now-sealed side plate.
There's also a small drain hole in the bottom that has to be sealed. I cleaned it out with a Q-tip and ran a siliconed screw into it, but just silicone or just a screw would probably be fine.
Next, whip out your 3" hole saw and cut a hole on the opposite end of the air box.
There's a cast rib that has to be ground down before you can rivet your new intake port on there. I used a 3" throttle body adapter for a Toyota (that somehow I didn't get a picture of) but any 3" throttle body adapter will work. I used 3" intake parts because this system was built around a Donaldson pre-cleaner I wanted to use and that has a 3" collar. In fact this project would have been quite a bit easier with 2-1/2" stuff.
Anyhow, enough foreplay. It's time to start doing real damage. Use your trusty 3" hole saw and pop a hole directly above the fuse panel. Placement isn't super critical-- there's actually quite a bit of room in there-- just make sure it's more or less directly above the fuse panel, because we're stealing that hole. Masking tape helps make a cleaner hole.
Clean up the hole with some emery cloth and keep sanding until your 3" intake pipe fits in there.
Everything I used except the pre-cleaner came from the intake isle at Pep Boys, so I imagine any big box auto parts store will have something that'll work. Anyway, unbolt the fuse block connector from under the hood, then unbolt the fuse block from under the dash. Setting both halves aside, whip out your die grinder and open up the fuse block hole until your 3" pipe fits in there. Connect the pipes (I actually used a single 6" pipe and cut it in half. I should have bought two) under the dash with a 90 degree elbow. It should look something like this, in the lower left corner:
"But wait!" you may be saying, "where will my fuse box go?!" We're going to move it down about five inches, cutting a 2-3/4" square hole in the firewall and reusing the original mounting bolts with some 1/4"x20 nuts and lock washers.
"But wait!" you may say again, "where will my PCM go?" The PCM (on my 95, anyway) has it's own harness that's like three feet long. I was able to swing it all the way over to the opposite fender and zip tie it to the existing harness for my winch and electric fan. You know, where the jack used to be.
This is the point in the undertaking where I noticed that my vision for this project had a little blind spot. I had not noticed that the proportioning valve and our new throttle body adapter would violate the laws of physics by simultaneously existing in the same place and time. To solve this problem I had to move the air box bracket forward about four inches, to where it almost touches the headlight plug. But then, just run the hoses and there we are.
So there we are, one (backwards) Hummer style intake for a YJ. I'm not quite happy with the angle of it and both pipes turned out a little short, but those problems can be easily fixed someday when the parts stores are open. The more traditional mushroom type pre-cleaner would probably look more streamlined. Also, I'm not quite sold that those universal hoses seal right. Once I'm done making changes it'll get custom hoses.