theres 2 filters. one is in the HFCM on the inside of the frame right under the drivers seat. there is a drain plug (hex) in it to drain the fuel out before you attempt to loosen the cap and take a diesel bath. once that is drained, loosen black cap with I believe a 36mm socket and swap out filter and washers. second one is on the top of the motor next to the oil filter housing (smaller of the 2) thats pretty self explainatory. loosen cap, change filters and washers, reinstall. as for prime, turn key to run position and listen for the pump to run, cycle key 3 or 4 times until you notice a change in pitch of the pump then the air is bled from the system. truck should fire, may have some white smoke for a little while.
Good luck, Jim