@alan: so the "thermistor " does what exactly ?? Is the thermistor some way to adapt a harbor freight head unit to a home made copper washer ?? Or is this necessary of you successfully get the worn out battery out of it's epoxy coffin as manufactured by trail tech?
Is there a way you have found to get a dead trail tech battery out and replaced with a new trail tech battery and then just use the old copper item that fits round the spark plug??
It seems the thread is a loose combination of any and all possible fixes with at least for me confusion on which approach each poster is following.
Much as I love and respect jbot he tends to demonstrate fixes that assume you have been looking at things exactly the way he looks at things AND you happen to be looking over his shoulder.
As an aside look at all the posting about rear hobbit pulley modifications. I keep looking for where one actually starts in the process of taking the two halves apart. For the life of me I never have seen the actual starting point. He assumes it's obvious. It's not !!