How do I remove the old pump

which pump oil or water?oil pump is inside oil pan must remove that 1st water pump needs frt of motor taken apart

I have done this job 3 times. For me, it is easier to remove the bed and you are looking right at the top of the tank. 4 or 6 bolts, removed with an impact, or 1/2" ratchet. Then ask a couple friends or a strong limb on a tree to assist you. Plus you can look the truck frame over for those other repairs that are common: axle u-bolts, shocks, rusty brake lines, cab corners. These are all problems for this model.