Reproduction heater box with A/C for 67 - 68 Cougars and Mustangs. This new plenum is made of a sturdy hard plastic that should hold up much better than the original fiberglass boxes. Includes pre-installed seals, clips, flaps, brackets, etc. Just install your heater core (with end cap seals) and AC evaporator (with rubber grommet). See related products.
The style of this box most resembles the 1967 version, with the flat mating surfaces between the two halves. The 1968 and later versions had a "jog" here. That being said, this box will fit 67 and 68 equally well. Given the rarity of unbroken original heater boxes, we're very glad this quality reproduction is now available!
NOTES: We've received some helpful feedback you should be aware of. First, since 1967 and 1968 heater boxes were a little different, you may find that one of the flapper control arms on this box is a little different than how your original was configured. This means you may have to adjust the fitting on the small vacuum actuator that controls it. Second, the large round foam seal that comes installed on this box, where it mates to the blower housing, is a much harder, denser foam than what was originally used, and will likely cause installation problems. Because of this, we suggest also purchasing the separate seal kit which includes a more correct soft, open-cell foam piece. We're working with the manufacturer to correct this, and will delete this text if / when that happens.
Check out our video below on how to replace a heater core! We used a '69 Cougar with A/C, but many of the same concepts apply to other years.