I've been posting this in the what did you do to your YJ thread and started thinking maybe I'd just create a cage build thread instead of posting it all willy nilly in there. For reference I'm using a Lincoln 135Amp welder with flux-core wire. I don't have a tubing notcher or anything, I'm doing it all with a chop saw and an angle grinder, which I don't recommend.
Here is a list of what I purchased to build this for those contemplating something similar:
Valspar Implement Paint (Enamel) - Low Gloss Black
All the add on bars were trim and notch to fit. The AtoZ pieces all came pre-notched, which is nice, but I'm not building mine exactly in the same dimentions as they were designed to fit, thus requiring trimming and re-notching.
Well, with those pieces in mind, here is how it all started: your standard 91 sport bar stock seats.
I started by cutting the rear sport bar and then cut the bolts holding the wheel well plate to the tub and removing the rear bar. Then I took and mated the new rear hoop bars to the b-pillar and down to a new floor plate. I chose to mate the rear hoops to the b-pillar directly behind where the stock spreader bar mounts (and where my front hoops ended up mounting). I think this creates a nice line in addition to a direct one point tie in between the Front and rear side hoops.
Then I went to mount the front hoop on the driver side, I mounted it just far enough away from the dash to allow use of the parking brake in the stock location. In the second picture the bolts in the floor are where my rocker guards bolt from underneath.
Then did the same for the p-side and ran the dash bar and front cross bar between the two front side hoops.
Then I re-purposed the stock spreader bars and used most of them to connect the b-pillar and the rear side hoop near the tub line and then took the windshield mounting bracket portion and welded them to the front side hoops to allow the windshield to bolt in like stock.
Once that all got tacked together, I built some hip bars and made sure that my full doors still closed and that they didnt' cover up any of the essential parts of the doors. After I got all that tacked together, the wife and I pulled the cage out of the Jeep to add some other parts and burn it all together.
Unfortunately I found that the floor on both sides behind where the b-pillar mounted was completely rotten. So I built some new patch panels from 16ga steel, using some cardboard to mock up and trace onto the metal. Great technique, worked really well for getting a nice piece. I cut out a bunch of the rot then overlapped a little with the new metal.
So far, I've just primered and put some black rust inhibiting paint on them until I get the holes for the cage mount drilled and new nuts welded in, then its going to get some bedliner like the rest of the tub. Did I mention I hate welding sheet metal?
It was about this time that I decided I should just go all in and upgrade my seats/tie them into the frame and add some harnesses. My Jeep is 99% off road, it sees maybe 1000-1500 miles a year road use, so I decided to go with harnesses instead of stock 3-point style seatbelts.
So, I ordered seats and harnesses from PRP. I went with their high back premier seat and 4 point harnesses. They looked like quality seats and were American made so I decided to take a risk and buy them without ever seeing some in person. May or may not have been a stupid decision, we'll see.
Anyway, onto more welding. I started by adding the overhead bars, v-bars in the windshield, and 2 gussets. The plan was originally to only have the u-hoop and 2 bars tied into the corners near the windshield. However, after some thought I decided a center bar to link the windshield v-bars to the b-pillar was a good idea and ended up with this:
Then, I rolled into the rear portion of the cage overhead bars, utilizing the AtoZ bars. I decided to mount the bar a little farther forward than Zach does with his cages. I did this because I shifted the rear side hoops back a little farther than they are stock and wanted my SuperTop's bows to clear the cage to allow the top to easily go up and down still.
After I burned that all together, I cleaned out the Jeep tub interior and sprayed it out then had my wife and our friend help me lift it back into the Jeep so I can mark and drill the b-pillar mount holes and when the seats get here, I can figure out how high to build the seat mount tubes.
Looks good but those door bars are going to be a huge PITA to deal with. They'll might not even work once you get your new seats in. I'd make them a little smaller and tie it into a tube connecting the A to B hoop. That tube could also be used as the start for mounting the seats to the cage.
For the windshield, I didn't bother with anything to mount in the corners. I just bolted it at the dash initially (CJs ran this way for about 50 years). The only reason those mounts are even there is to support the added bars that were added in the YJ sport cage.
After a while I decided it was a pain to bolt the windshield on at all so I started using a lashing strap through the factory tie-down hook in the middle of the windshield, and looping it around the cage. Between that and the removable pins I added in the windshield hinges I can completely remove the entire windshield in about 2 mins (unplugging the wipers is still a pain).
The hip bars were mocked up and installed to clear the doors and stock seats, I burned them in before deciding to go with some new seats so that may have to change, but if I can get the seats and stuff in with what i have now I'm gonna leave them. The decision to just go with new seats and harnsses really stemmed from me removing the stock b-pillar and finding all the rot underneath. The areas the stock seatbelts mounted to was trash on the driver side and not much better on the passenger side. I decided that instead of shelling out money to re-do the stock style, I would bite the bullet and tie the seating and belts into the cage properly.
For what its worth, I got the dimensions of the new seats and was trying to lay out in my nugget how I'm gonna build the seat mount bars and I think they will work, but we will see when they get in. Additionally, my rig is not a DD or even really a street Jeep, its my trail rig so ease of climbing in and out is a small factor in my design, hence me going with a deeper suspension seat and a harness setup.
Regarding the windshield connector bars, I may end up canning them after getting feedback from multiple people about it. I realized the CJs never had them, I just figured it added some rigidity to the windshield. I don't really like how they came out anyway.