You will want to wash the ender side of your jeep very well first, so when youre removing it, dirt does not contaminate the tank. Specifically where your gas lines reach up to the filler neck.
You best bet is when you remove the tank use two jacks, this will ease the process. On top of the jacks, have a thick peice of plywood to have as a flat surface for the tank to come down on.
My best advise as well is to take off the filler neck and hoses before you start to remove parts. Start by removing the outer neck where your insert a nossle for gas. then remove the two tubes attached to it an the tank, these must be removed anyways because you are dropping the tank. Removing these will give you the oppertunityt o replace the clamps with newer ones, also it will give you a oppertunity to check your filler neck for rust, etc.
After you have the plywood up, apply a bit of pressure with the jacks on the tank untill the jeep lifts up about 1/4" to 1/2", anymore is overkill.
Next remove the bolts and proceed to let the jacks move the tank down. Note that there are two bolts on each side that do not need to be removed. They hold the metals straps stetching on top of the tank. You can remove the tank with the straps on.
Once everything is removed, SLOWLY lower the tank. when you get about half way down, you should be able to put your hand above the tank and start to remove the clamps and electrical harness. A bit of advice would be to use some needle nose vise grips to pinch the gas lines going to the tank, this way it will not spill all over your when removing the lines.
After everything is removed and pushed to the side, proceed to lower the tank and after your finsihed doing what you need to do, installations is reverse of removal.