Here is what I would do.
Go to Tandy or Dicksmith or Jaycar and get some heatshrink, theres a certain one you can get thats also got a glue on the inside. Its called 'dual wall' 8mm diameter. About 9$ a 1m length from memory. Do not use anything else.
Go back up to the coil side of the carb. Clean the insulation on the lead, cut the lead, strip 5-10mm or so, do the same on another lead off a full crank and solder them together. Do a good job of it so its a good solid connection. If you do not know how to solder research it.
It goes something like this.
Plug in the soldering iron and find the solder.
Sit the two bits of lead in place and measure so you have the correct length. Cut two bits of heat shrink, first piece on the join lapping the wires insulation by about half an inch or more both ways, then cut another bit for over the top that goes about another half inch each way again.
Take the plug end bit of lead to the vice and screw the screw up the centre. You need to have the end poking out of the vice a bit but it sure is easy to do it this way.
Put the end cap on and mount the lead to the plug, shape the lead to the way it lies on the motor and that will hold your join in place so you can solder it hands free.
Remove the cap/cover.
Heat shrink on, work from one end to the other as you shrink so you do not get a big bubble at the join. Let it cool before putting on the second layer of heatshrink.
That will give you a good solid water tight connection thats fool proof. I have done this countless times on power torques with damaged leads and never had an issue. 99% of the time i join a reclaimed bit of full crank lead to the power torque lead.
The full crank lead is a PVC tup coating and fairly stiff.
The power torque lead is a softer more jelly type silicone stuff (like a car lead) with a thin outer pvc coating.
They are diffferent diameters, the power torque is fatter.
A small shot of WD40 in the cap before you put it on helps.
Cheers.
