If I may expand a little on Twolane's post, I'd suggest first doing the circuit breaker, either by replacing it with another circuit breaker or doing the Maxi-fuse conversion if you prefer. This recommendation is based on the reported failure mode and the history of the breakers from that period. I would defer the ignition switch replacement until I determined the circuit breaker change didn't fix the problem.
This recommendation is based on my normal desire to understand exactly what the problem was. Using the shotgun approach of changing several components at one time will not tell you what the real problem was, and if it comes back a year from now you will be right back where you started, not knowing which component is causing the problem.
JMHO - Jerry