A/C to Heat ONLY conversion on 68 Dart Sports Special
Another way is to buy an aftermarket heater. I saw one the other day very small, for about 200 new Look ebay, too.
Here's one, very small
https://www.summitracing.com/parts/...-flex-a-lite&gclid=CIbV2sbortMCFUGTfgodkJoD9g
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