yes, i already new about the glove boxes being slightly larger on the a/c cars and not fitting the heat only set up. i actually also have a complete extra heat only set up stored away . complete with glove box, hvac control panel and harness.I did a heat only 79 Monte Carlo dash swap with an A/C dash out of a 86 El Camino. If you are using the non A/C set up which physically will fit behind an A/C dash you have to keep the back pocket from your non A/C glove box. They are different between the heat only and the A/C cars and must be used accordingly. Otherwise it should be a direct swap. I ended up using a 81 burl wood inlay for the passenger side and just added a section of black plastic behind the vent on the passenger side. Below are some not so detailed shots of the dash in the 79.
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