Could be either the hose or the heater core. Much easier to drop the heater core in the 641/2-66's than the 73' Torino. The heater cores are very inexpensive. I also suggest buying 8'-9' of 5/8" heater hose and replace them too since it is very easy once the heater box has been removed. Optionally, you could also order a seal kit to complete the job but it is not required if all you want is the leak to stop.Dennis, We own a fully refurbished 64 1/2 Mustang that we bought about 10 years ago. Yesterday we noticed that we were leaking anifreeze on the passenger side. Is the only reason for this a bad heater core-we never use the heat as it is a convertible and we only take it out in nice weather . My husband replaced the one on our 73 Grand Torino Sport and he had to drop the dash. Your instructions look like this is a much easier job to do.
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