Weigh the time it would take save the $$ to put in decently better parts all around versus the time it would take to rebuild it if something went wrong. You don't need really pricey parts but a solid forged and properly put together bottom end will last you a while. You can also spray it without much concern. For a few hundred more, a forged steel crank will be worth it in the long run.
http://www.summitracing.com/parts/es...make/chevrolet