IMO, Pinion snubber = door stop to let a breeze in the garage. I never use them, EVER. If the rear springs are good, clamped, it's an unnecessary item, a crutch. Low 10 and hi 9 second leaf spring A body cars... no pinion snubber in sight! :) You got your own data about whether they work.
Be that as it may, the problem he is encountering is simple spring wrap and then a violent counter reaction. A pinion snubber would be the simple fix. As Howard just explained though, a snubber is not practical for his particular application. Plan B in this case would be a simple pair of Slapper Bars. Since he's using a Dana and so does not have to worry about distorting the housing, Slapper bars would be a quick, effective fix. If that works to cure his basic problem, then he can move forward to the next step and work on the springs.
