if there was water in the crankcase and it was run for any period of time, you need to replace the rod bearings at the least, mains would be a good idea as well. Gauranteed if those rods were run with water in the oil it will spin bearing usually very soon after repair. Mielage on the truck is a big factor as well. I would have the heads worked- valve job ect. looking at about $150 a head and they will adjust the valves when they clean the valves. Head seat is about $120, bearings run you about $50.
You could bring me the whole truck and ill do a complete rebuild on the motor- $2500 - line honed/bored, reconditioned rods, polish the crank, bearings, pistons, rings, heads decked, valves adjusted, valve seals, and a valve job, all new seals. youll be good to go for another 100k