the glug glug, or gurgling sounds could be air in your heater core. take both hoses off the back of the alt, then flush with a garden hose, after you flush it, fill both hoses up, and quickly get them back on the engine.
if your heat feels weak, this would defiantly be your problem.
if you take the glove box out, look to the left, but up by the front of the dash, you cant miss the vacuum actuator. it has a vac hose to its round, about 3 inches across. its in the pic with the actuators for the blend doors in that link up a few posts.
