TR6 Horn Relay

[ASesso@aol.com]

I am restoring a 1971 TR6. I have installed a new wiring harness and have a  
question about the horn relay connections. The car has a round red Lucas relay 
 with 5 spade connectors. 4 around the edges and one in the center. The 
wiring  diagrams I have all show this relay with 4 spade connectors. From my  
understanding 4 wires ( 2 purple 1 purple/yellow 1 purple/black) run to this  
relay. The spades are numbered. What is the fifth spade connector for and how  
are 
the 4 wires attached?
                      thanks
                         Art