Can I do this without removing the engine?
BTW Its insane to design something like this(have no Oil pan and putting the crank case inforcement thing over the *#%^@*$ Oil pump).

 

I tried it on my 2.8. The manual says it can be done by jacking the engine up at the mounts with a 2x4. Don't believe them. If you are persistent you can get the pump off, but will not get it back on. Plus, the oil pan gasket is nearly impossible to get back on that way. I know it sounds like a lot of work, but pulling the engine is a better option.

 

WHEN THE MANUAL SAYS THIS IS A VERY DIFFICULT TASK REQUIRING SEVERAL SPECIAL TOOLS AND REMOVAL OF THE ENGINE FROM THE VEHICLE...

You should back away close hood and scrap it...

Nothing on the 4.0L SOHC can be accomplished in the truck if you have to remove that sorry excuse for a oil holder on the bottom end you will have the engine out it will leak oil for the rest of its life...

Its far easier to pull it do what you need to do and put it back in than attempt anything in the tight quarters under it.

 

Yes, however on my 4.0 4x4 I did have to drop the front differential to remove the upper oil pan (ladder)