Very simple fix......

mycuda said
The ujoint couplers I use have D shaft hole for reason you said. Need to grind down both sides of shaft to allow entry into joint lockdown.
allen key and locknut cant possibly spin.
I'm just trying to show people other options out there.
basically all rack pinion use this

D.

Right, but rack and pinion steering shaft's have sliding sections like the one I installed, making the sliding joint unnecessary. Installing a u-joint into the old system changes the ability of the steering shaft to deal with that motion. And the older unibody cars flex a lot more than the new ones do. So just because a modern car with a rack and pinion runs a plain u-joint doesn't mean an old A-body can do it the same way, there are different problems to address.

StephenShaw said
This subject has been around a long time. One older post said to video the joint driving around to see if normal (not accident) driving shows movement in the joint. Someone posted a video and you will be amazed how much flex there is in the body requiring this joint to flex in/out.

Yeah there's a TON of flex in these cars. And one of the worst places for it is the front end of the car ahead of the firewall. Because all the suspension loads are carried by the crossmembers, there wasn't a lot of reinforcement added to keep the rails from flexing up and down. That's why the firewall to shock mount/frame rail stiffeners are such a good addition.