atomarc,
you're right, my bad.
The way I was thinking would require another switch to control the relay so that it could be turned on when the starter was needed, and then turned off to keep the relay coil from overheating. I didn't think it through hard enough.
You could probably use a lever-type brake light switch actuated by the starter linkage to operate the relay.
Or, I wonder if the R-200A relay is actually rated for continuous duty? That's the concern that started all this.
Their #67015 is, but it only handles 85 amps.
regards,
Leon