OK, I am looking at the back of my '74 CJ-5 trying to figure out a good way to tie the cage to the frame. Front hoop is no problem. back hoop, problem. It looks like any tie in will interfere with either wheel travel, or the gas fill hose.

Anyone have pics of a good way to do this?

The best solution I can come up with is to put a X brace from the corners of the main hoop down to the floor behind the seats and tie into the frame there, and leave the mounting points on the wheel well just bolted to the body.

That's probably a good idea. You often see that setup on race cars.

Anythings better than nothing in the frame tie in , but it's hard to do. You just do the best you can with the constraints imposed on us by the wheel well, frame width, etc.

There are typically outrigging curved tubes (J shaped) welded to the frame at the rear. Problem with that design is that tubing has it's best strength in compression, so straight tubes are far stonger. But a straight line from the rear most bar on my jeep would put the end outside the frame. I see those cage tie in kits sold in the catalogs, and I picture how weak it must be to have an angled roll bar terminate on top of a verticle tube. Any impact would simply bend the vertical tubing, something which it has little resistance to. I think if you wanted to build the cage really strong, you could have to triangulate the cage to frame tie in's. Either that, or you are only building for an upside down pure vertical impact.

If someone has a good rear tie in design and could post some pictures, we would all benefit from your knowledge. Thanks.

Here is how the rear most tie-ins are on mine. They don't interfer with the tires or anything else. This picture is on our CJ7 with a different style cage, but I had the same thing on our CJ5 w/o problems.

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Pbmcauliffe, I like what you did on the cage tie-in there. I had the same idea but was worried about tire
rub. Glad to here it works. I was curious if that was the only tie-in or if there was another toward the
front of the wheelwell also?

That is what I thought it should look like, but there isn't much room on my -5 back there. Guess those mud deflecting panels will have to come out.

Since it is a CJ7, the front part of the main hoop comes down behind the front seats. Here is that tie-in.

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Thanks for the pictures PBMCauliffe. The tie in's look good. Hope this doesn't sound too critical and maybe this would be a waste of time, but I would triangulate the tie in's you have. The one going to the base of the main hoop is at such an angle that it would only provide strength in a fore and aft direction. It has little strength up and down, and the length of the tube adds leverage to rip it off the frame if force was applied upwards. If you welded a triangle of steel between it and the top of the frame it would have tremendous up and down strength too.

The long tube that runs up to the rearmost bars inside the wheel well looks good, but could also be made better with some triangulation. If there is room directly above the frame (and it looks like there is), a second tube forming a triangle could tie in with it right at the top where it goes to the plate bolting to the base of the cage. That would give it strength in the fore and aft direction. I think it needs some because it is so high above the frame, and the angle formed between the two bars where they meet.

Did you notice any increase in vibration having mounted the cage solid to the frame? I'd do that too if it's not that bad.

The rears are vertical from the side, so the only way to triangulate them effectively would be forwards, then they would interfere with the tire, if I understand what you are describing.
The middle ones could be made stronger with the plate as you described, currently there is a just a large plate under the body that is thru bolted to the cage's lower "L" to resist up/down forces.
The front hoop tie-ins and the thru the firwall tubing is all solid mounted, but the addedd vibration isn't too noticeable. It isn't a daily driver though, so maybe that's why it doesn't bother me.