No Spark on 1990 - 100HP Mercury Mariner

[comstox]

I am diagnosing a no spark issue on 1990 100HP Merc Mariner and I feel the culprit MAY BE the kill switch. I have, what I hope to be, a quick question that is easy to answer.
IF THE KILL SWITCH really is bad, would I still get spark, but the engine just won't start, or does the kill switch somehow prevent spark?
To test spark, I am using a in-line visual spark tester. (One where you pull the wire off the plug and IF SPARK is good it lights up like a light bulb.)

Thank in advance ignition gurus!

 

[Faztbullet]

Kill switch ground the switchbox thus NO SPARK. What is engine doing and what tests???

 

[comstox]

Sorry I don't have much time to diagnose today, but what if I just disconnect my black/yellow stripe wires from the Switch Assembly?

 

[comstox]

We just disconnected the two black/yellow stripe kill switch wires from the Switch Assembly and WHAM!!!!!!! (Not George Michales,) ad we got the boat started!!!!!!!!