[spuggy]

That's a modified car. Middies have most of the advantages of the later cars, and weigh less than SC's -even if you add the SC flares later. The only panel that might not be galvanised on a '76 is the roof, and even late production '76 MY have that. You might be missing boosted brakes on a '76.

If you're looking for a driver to keep and enjoy, it could be a deal - depending on how well-sorted it actually is (does the oil temperature read accurately? the 3.2 sender is not matched to the '76 gauge - that might be an indicator as how well/thoroughly the rest of the mating up was done). If you intend to drive it hard, you will probably eventually want later brakes, upgraded torsions, maybe SC flares and wider wheels/rubber. Which are all additional modifications.

As for selling it afterwards, well, you can rule out the purist section of the market... You start to get into matching a buyer's ideas of "good upgrades" with yours/what's been already done to the car. Which can be done, but it's potentially a lot harder than selling a stock car.

Although the price doesn't reflect the cost of rebuilding/installing that motor correctly, it does seem a little high - you should be able to get a good 3.2 for that money, which came from the factory with most of your potential upgrades (or at least partially there), and is entirely stock.

All of which might be irrelevant if you never sell it. But circumstances/intentions can change.