I've not had one of those apart but I'd think you just need to remove the two screws & split the case then replace the wire. A white lithium grease should work ok in the transmission. If someone has experience with this operation and I'm wrong please educate us both.

Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.