Can someone advise me on the least = expensive way to repair a leaky rear heater on an 84 Vanagon?  I have pulled the = heater out.  Seems like a lot of plastic is used to seal things up.  = I imagine that the heater sells as a unit, motor, core and all.  I = also have a leak in the valve that is used to cut off the water to the heater.
 
Thanks,
George
Columbus, GA