From what I can tell the engine is in the FE/FT engine class, making it a big block engine, regardless of displacement, as long as it will turn over, the engine should be worth selling for better than scrap.
For the general body style that the truck is, 67-72, I cant locate any with a D engine code.
It could be any of the following engines- 332/352/360/361/390/391/406/410/427/428.
All desired by hot rodders.
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