Does anyone know how involved it is to pull and rebuild a 5.7L Hemi out of a Ram 1500 (4x4).

My young (idiotic) cousin went off-roading in his truck and got stuck. He and his dad, who know next to nothing about cars/trucks, say the engine is "hydrolocked". But, the story is that he went mudding, got stuck, and in the process of trying to get unstuck something happened to the motor and it doesn't run anymore. I don't see how he could have gotten water in the engine just sitting in one place spinning the tires and I also don't see how he could have over revved the motor because of the rev limiter on modern engines.

So, any guesses as to what could be wrong? They were asking me if I'd be interested in rebuilding it, and I said "sure".. but I don't know much about anything other than the 6G72. I'm sure it can't be too hard though.