Originally Posted by Hackd

Most likely what has happened is the rubber on the stator plug has deteriorated and the metal terminals inside are now moving. Not uncommon. Really bad design by The MoCo.

Cheap and Easy Fix:

X-acto knife, small 'dental' style picks, carb cleaner (or other spray cleaner), and some fine needle nose pliers.

Shave a bit off the connector that passes through the inner primary.
Douche the connector with the cleaner. Clean the regulator plug too.
Use the picks, stick it through the stator plug rubber to get under the metal terminal connector and push up a bit.
Use the pliers to pull the metal termnals up (not too much) and then 'snug' them a bit to make the connection tighter. They are just a split tube that has spread apart.
Take the regulator plug and while you still have the picks poked through the rubber on the stator end, snap the male ends into the female stator.
You should faintly hear the click and also feel it.
Done.

It won't do any good installing the part Beemer posted, unless you're getting a good connection. Once that is done, you can put one of those on. I didn't, and have had no problems.

I did this back in 2006. I had never gone more than 2 years on a battery before then. The last (HD) battery lasted 8.5 years, and I only replaced it (Big Crank) because it was sounding a bit tired when the temperature was below 50 degrees.