Laurence:
You may want to get a spare diode as well, its the u shaped wire between the center 2 studs. (the part number on mine is TCI 1N540, it's a 3 amp rectifier diode). During replacement of the starter solenoid on my coach it shorted out. They are hard to find since Auto Parts stores or home electrical stores do not carry them. I found my diodes searching the internet, an electrical distributor in Florida had them for $.20 cents each. I know have spares to carry along with the solenoid.
When the diode shorts out, there is no dash power of ignition start function. I found out that if the diode is removed dash power returns, since it is between the ignition wire and ground wire on the solenoid. I also learned through help from Mike and Steve that the strip on the diode goes to the incoming positive battery cable (left side of the solenoid).