The seal groove and bearing holes must be concentric for a lip seal to work. The seal area was cut before the final bearing surfaces were honed, so they are not a perfect match. Pontiac did the same thing. You need to find center of the bearing surfaces, then cut the seal groove to that center. The few that use the lip seal and don't have leaks, get lucky that their blocks are closer to centered that others. Lips seals don't have a lot room to be off center. The older Cummin's 5.9 had terrible lip seals on the front, they used a plastic sleeve between the seal and crank to center the timing cover before you tightened down the bolts on the cover and they still leaked. We used to install two seal per engine just to slow down the leaking. The bearing clearance let the crank move around and the seal didn't have enough lip to compensate.
For years guys in the Pontiac world tried lip seals, most all of them leaked. The trick now is to use a one piece rubber seal that you make a clean cut across, roll it on to the crank, then fill the seal groove with sealer. As you install the crank, the sealer fills the voids of the non concentric groove. Once it dries, the seal is held by the sealer, not the block.
Thats a good looking packing tool, the Pontiac one looks the same only they cut a radius on the crank side to compensate for the curvature. It should work good, just keep an eye on the seal as you whack it into place, you want it tight but not frayed out everywhere. The engine will be quite stiff to turn over for awhile once done.
