Something wrong with my truck. Any ideas?

My truck lately has been heating up really quick. And as i'm driving i hear what sounds like water or some other liquid being dripped on my motor and it steams up and smells funky. And now when i throw it into reverse i hear a rattle sound. Don't know what's leaking or rattling. I have a 1994 ford f150 straight six motor 4x4. Any ideas on what's going on? Easy fix? Expensive?

Typical Ford

Water pump shot is my guess. Look for water dripping out below the shaft area of the pump. There's a weep hole there that releases water if the pump seal goes bad. Could also just be a bad hose, either on the engine or heater core. Or maybe a freeze plug in the block or a small leak in the radiator itself.