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Discussion Starter · #1 ·
Anybody ever replaced a heater plenum without removing the underdash air unit? Eesh! The old one came out in pieces (plus the P.O.'s duct tape) but getting the new one properly positioned to hook up the defroster cable has been a bear. I did make some interesting discoveries while under the dash, though. Only one of the three cables that control the heater, defroster, etc., was hooked up, and I also found some electrical connections that needed to be plugged back in. More stupid P.O. tricks!


1965 convertible "White Pony", my own lesson in mechanical humility
1968 coupe "Jedstang" for the soon to be 16 y/o boy

1,488 Posts
You have to unbolt the heater box from the cowl vent under the dash. You can't miss it, there is a little bracket fron the top of the box. Also, you have to unbolt the heater motor at the fire wall from the engine compartment, 4 nuts. The plenum has 4 small screws, you'll see. You don't have to yank the heater box completely from the car, just loose enough to work in that back corner.
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