I need to replace my heim joints on my control arms and need to put a bigger heim...problem is, how do I get access to this nut where the control goes???

 

IDK for sure, but that looks like a "weld" nut, that is one that's welded to the frame before it was assembled. It looks like it's clear so maybe you can rethread it.

 

It will move inside of there but it's got a tab or something to keep it from spinning.

My wj has some long arms made out of dom tubing with Johnny joints and heim's. The heim's I'm having issues finding the correct size. I was going to replace them with a 7/8 bolt heim and be done but can't get access to the nut. Looks like I could cut the back out and get in there but hate to do that....way to go jeep, way to go.

 

So it's not a "weld" nut, but a "cage" nut. The problem is, IDK if the sheet metal will withstand a 7/8 bolt without tearing out. You may have to weld brackets for your long arms.