Electronic Distributor pig tail

[k3522]

The two wires coming out of the distributor are a negative and postive.
Which is positive and which is negative?

I am purchasing:

http://store.summitracing.com/partdetail.asp?part=SUM-850081&FROM=MG

 

[dgc333]

The black wire is negative and the colored wire is positive.

 

[k3522]

thank you.