Starter Relay???

[thisolechevy]

Before I get started I do understand that this is a Ford question, but hey its my dads car. We have a 1959 Mercury Monterey and until we started to "restore" it it ran! We just took off the water pump and removed the radiator because neither worked. Just today I reassembeld the car and tried to start it, it clicked and then all power was lost. I know that the battery is good and all the connections are in good cond. The weird thing about it was all electrical worked until I tried to start it, then it was all gone. If I simply disconnected the battery and waited a little then reconnected it all electrical worked great So is the starter relay bad??? or am I just missing something obvious