2000-2500 at 65 would be a better speed, as the manifold vacuum at 1700 will be so low the power valve in the carburetor will stay open all the time.
It's possible to over-gear an engine to the point it can't develop enough torque to pull the vehicle along a level road reliably, and even a slight hill or an attempt to accelerate or pass puts it into a "lugging" situation where more throttle opening doesn't produce any more RPM. Both performance and gas mileage take a big hit at that point. With that rear end you'll be spending a lot of time downshifting, and forget about ever getting the torque converter clutch engaged.
Jerry
