doesn't matter what balance crank you buy as long as the balancer and flywheel match up to it...... i reccomend finding a good shop that does balancing and asking them this question... they'll give you the best help on it.... i dont think in the year motor you have there was the internally balanced crank yet.... i believe those weren't til 80 somethin... but i could be wrong... might be nice to upgrade to one of those fluid balancers when you get the crank though.... keeps the balancer from slipping