New Plug Wires

I am changing the plugs and wires on a 1991 ski nautique and the wires that they said we needed do not work.  They have two different ends and I have been told that these wires go on older model chevy engines but they do not work on this engine on this boat.  I have attached pictures of the wires to see if anyone knows what these are for, only one end looks like the ends on the old wires.  There may not be enough info here but dont know exactly what would be needed.

This picture is the same as the boat I am trying to change the wires on.  Is this the protec system?  In that thread it says to try changing the plugs and wires before converting to a new system.  Just trying to be able to identify certain things.  

Thanks Jonny Quest, thats what I needed to know.  I have not determined that the ProTec system is failing, but I did read in several other threads that before you replace the system, try changing out the plugs and wires.  

This all started when this boat was bought and it was said to be "cold natured."  It would barely run for several minutes until it warmed up, and then one day it sounded like it backfired and blew the side of the muffler out.  I took the old muffler out and it basically crumbled as I worked the pieces out of the hoses connected to the manifolds.  I am almost certain that it needs the carb cleaned or rebuilt, but wanted to try the plugs and wires first and go from there.  We have put a new muffler in which was fairly easy but do no want to have it blow out again from a backfire, if thats what it was.  I was there when it happened and really did not hear a backfire but I was at the bed of the truck when it was on the trailer getting cranked.  When we lifted the motor hood water was running out of the side of the muffler and thats when I figured it had backfired into the muffler.