I pull block drain plugs whenever possible. A 460 holds many quarts in the lower water jacket. Even the smaller engines hold quite a bit.

By using the radiator drain, or pulling the lower radiator hose, all the water in the block below the water pump passage level stays in the block. There is an upper common area, that pulling either side's block plug will drain. And a lower water jacket area (one each side of the engine) that only the plug on that side will drain.

I've pulled out the driver's side block plug on the '97 4.6L with no problem. Can't tell ya what wrench I used, don't remember. But it was no big deal. I used #1 Permatex (the setting type) on the plug threads before putting it back in.

Block drain plug on the passenger side on many V-engines are blocked by the starter. Pulling those on old engines can be a good idea. May pull the plug... and nothing comes out! Have to poke a thin steel rod in to dislodge crud, or casting sand that collected there at the bottom of the water jacket.