I've read the oil pan can be replaced in the truck but you "may have to remove the drivers side motor mount bolt and raise the engine up about 2" to gain clearance" on some models..
I think the 4x4 trucks it'll drop down without having to do that,or not be raised up much if it has to be done..the hardest part will be getting the pan back up in there without smearing all the RTV or gasket off against all the obstacles...I could only get a cork 2 piece gasket in Fel-Pro-no one lists a one piece one here,that I could find..not for a 6.2 anyways,only small block gas engines..
The oil pan in my truck has been rotted and leaky for a long time--I have two good used pans I can swap on it--if I could lie under it that long...
I have begged my friend to replace it for me on his lift,and I'd pay him whatever he wanted,but he's scared of my truck,knowing everything is so rusty it'll likely become a big headache,and he fears if the oil pans I have turn out to be "wrong" it'll be stuck on his lift for days..
So,instead of trying to replace it myself and risk not being able to complete the job---I have fudged it by using J-B Waterweld putty,when that failed after a year or so,I drained the oil,let it drain a full day--then washed the pan off good with 2 cans of brake cleaner,wire brushed it and got all the scabs off--and I put two bolts in the spots that had become holes (one bolt is a 7/16 flywheel bolt!) and the other is a sheet metal screw about 1/4" diameter..
The crank doesn't go very far below the block's "rails" where the pan bolts on,so I was not worried about those bolts hitting anything..they are short too,maybe 1/2" long..
The only thing I'd be worried about on your oil pan is if it caved in where the oil pump pickup sits ,about 3/4" off the bottom of the rear part of the pan..if it got dented there,it might restrict oil flow,or have dislodged the pick up screen from the tube..you could probably just use a slide hammer dent puller to pull the dent out and plug the hole with a screw,braze it,or J-B weld,if you think the pick up screen & tube is still OK..
I coated the entire leaky area on my oil pan with Mar Glass short strand fiberglass body filler,and I had two more pinholes appear further away I "missed" and didn't see,so I used a shop vac on the oil filler pipe to apply suction to stop the drippage and I sprayed it clean with brake cleaner and applied Permatex black RTV to the pan,and so far,it has not leaked at all in a good year--from the oil pan at least--it does have another leak somewhere around the oil cooler hose ports,but its minor,I only need to add a 1/4 quart once a month or so..
I'm hoping by the time the pan needs replacing ,the truck will be "done" and parted out or sold by then..