http://www.oldengine.org/unfaq/
Try this site it shows a drawing of how to do it and the part # for the solenoid
also reason to mount the solenoid in a different spot is because of the heat. Chevy starters has the solenoid mounted to the starter just a little to close to the headers so after it heats up to many times the starter dies also the hammer trick will only work so many times then your stuck on the side of the highway I know form experience that is why I went on to the next trick . I mounted mine on the inside fenderwell. good luck