Greg,
Don't know about going to the fuse box, doesn't on my '69 XR7 'vert. It goes from the switch through its own grommet through the firewall and then to the solenoid (through its own inline fuse holder).
No one rebuilds the top cylinders to my knowledge, just imported repro and domestic, imported are a little cheaper. Shop for best price, ask which ones they are and evaluate on those criteria, that was my approach.