1993 ZJ AW4 4.0 I6 Starts and runs fine, as soon as I shift into Drive/Reverse it dies. Sometimes right away and others it will sputter for a few seconds. If I give it gas it will lurch foreward a bit then die.

-Replaced the Fuel Filter, Spark Plugs, TPS, IACV,
-Tested Fuel Pressure at the Rails reading around 40PSI
It will stay in gear if I shift my Transfer Case into Neutral, I;m not exactly sure what that signifies but it may help. I've heard it could be the Torque Converter, but I want to rule out every other possible thing before I drop money at a transmission shop.
I love this Jeep and WAS planning on using the money I had saved up lifting it, not getting it running but it happens.

 

Check for vaccum leaks. I've also heard of the neutral saftey switch causing this, but that part is rather expensive if you get it at a parts store so I'd start looking for vaccum leaks first. I don't think your torque converter would cause this. Could be wrong though.

 

It is possible the torque converter clutch is locked up. Usually either the stator or the turbine is the problem, but in those cases, it either won't move or will be a dog on acceleration. It's possible the lock-up solenoid is energized at all times, thereby keeping the clutch engaged.

Try putting it on jack stands, running it in drive and hitting the brake. If it runs fine and stalls when you try to stop it, it's probably the converter.