Driveshaft orientation, '72 Duster 4 speed

With a 4-speed, you should probably run 7290 or better U-joints. So, if your shaft has one 7260, and yur not running a driveshaft loop, I would install it at the rear. That way, when she breaks and and the driveshaft falls down, it doesn't catapult your car into next Tuesday.
the whole driveshaft catapult has been disproven.

catastrophic damages, yes. yeeting a car to the week next, no.

big u-joints and DS loop is always a good idea.