If you decide to drill & tap the crank snout, use a stud, not a bolt in there to draw the balancer into place. Putting turning stress on the thread tapped into the crankshaft will strip it out in short order. If a stud is screwed into the crank, and a nut & washer is used out front, the crank thread is less likely to strip since the stud isn't turning.
On my race engines, I use a needle-bearing balancer pusher with a 1" fine thread that I bolt to the end of the crankshaft with a long bolt, then tighten a big nut down against the face of the balancer with a Torrington bearing between hardened steel washers carrying the thrust load. The pusher takes a 1 1/2" socket or end wrench to turn it.
BTW,a small-block V-8 center bolt is a 7/16" X 20, not a 1/2".
Jerry
