I'm trying to fix a coolant leak near where the heater inlet meets the inlet hose. I am stuck trying to remove the heater core. Between the drain tube thru the firewall and the metal framing on the lower dash it just won't come out. Does the dash where the heater controls are located need to be removed? Not sure if that is even possible. The PMD service manual seems to be missing a few steps and is really no help. Any suggestions? Thanks.