The heater was apparently leaking and the metal hardware of the heater box is rusted. After taking everything apart I started the process of cleaning the metal hardware and soaking the parts in Evapo-rust.
I found out that the heater core did not have the rubber seals to hold it place in the heater box, so I ended up ordering those seals. I also ordered a replacement blower motor resister assembly since I have everything in pieces
I did order a seal kit for the heater box and also a plenum chamber.
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