Beds are fairly easy with an engine hoist, IF it's the style that has extendable legs. Shortbeds are cake; a longbed is a little bit too long but you can still get it done if you're careful. Remove the tailgate to help with balance, and run a pair of heavy duty ratchet straps in an X from the holes below each stake pocket. Lift with the hoist at the cross of the straps.
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You see where the ram is sitting right up against the back of the bed and that's on a shorty, that's why I say it's tricky with a longbed. You want to extend the boom as far as it goes, so you also want to extend the legs so the whole mess doesn't topple over. Be careful.
I would imagine if you had the wheels off one side and frame on stands, you could come in from the side on the longbed, too. Just a thought. I haven't done it that way to remove a bed, but I did lift from the side once to replace a fuel pump on a longbed. I just ran a strap across the front stake pockets and lifted that end.
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Richard