Whines on acceleration ??

Hello All,

I recently purchased a 74, 360 duster and the car whines under acceleration. It happens when I put my foot on the gas just a little bit, it will start whining, and then whenever I pull it off, it immediately stops. Coasting is quiet. It's actually hard to hear where it's coming from, but I'm assuming something in the rear end. It's a 727, with a 8 3/4 suregrip 3.91 gears. Under WOT it seems to go away.

Just wondering if this is "normal" for this type of setup, or there is something that I should look into.

Thoughts ?