If you convert to an alternator, convert to HEI, add A/C, use high cfm electric fans and things like that, Bosch-style relays are in my opinion a great and in some cases necessary choice. The ramp-up amperage on an HEI distributor will cause failure in an older style ignition switch...even one that was rated for 15 or 20 amps. I can mail you one which failed magnificently...the contact points lasted only a few weeks after the conversion. By converting to relays you'll be standing on the shoulders of GM engineers who began doing this around 40 years ago. Good luck.
