Unless the Chevy V8 is a late model with a full circle seal already there, there's no way to run one on the older types with the big flywheel flange. It's possible to weld up a damaged seal surface and regrind and polish it to original diameter, but it's cheaper to buy a new crank. Stick with a quality 2 piece seal like Victor or Fel-Pro, not the cheap offshore knockoffs a lot of FLAPS sell. Make absolutely sure the main bearing clearance is down to minimum specs to keep the crank from bouncing up and down on the new seal.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!