Originally Posted by MoC
Stop what you are doing right not and go put a jack under the bellhouse.. The piece you removed is what supports the transmission, tcase, and the back of the engine. Without it all the weight is on the motor mounts. There is a good chance that you now have a broken mount and if you are not careful it all could come down.
This^ and if its a 258 the rear of the valve cover was supporting a large amount of weight, by resting against the firewall.
If its the 258, hopefully you didn't crack the cover, or punch a hole in it with the stud and nut thats directly behind it. You'll know as soon as you drive it. Watch for oil under the jeep.