This method assumes your switch is not physically damaged.

what's needed:
3/32 drill bit and drill
#4 torx bit/driver
fine grade sand paper
contact cleaner(if you have#

3/32X1/4 pop rivets or small bolts and nuts.

Make your tests with the attached diagram to verify bad switch.

Mine would test good then bad etc..

drill out the 3 pop rivets#first#
remove the #4 torx head screw.
becareful !!the portion you are removing is spring loaded.
make note of the spring and the way the small rocker plate is positioned in the bottom of the housing.#50/50 chance of putting it back)
clean the contacts at the bottom of the housing and also the contacts that are spring mounted to the small rocker piece/board.
I used 3m p150 flex sand paper taped to a pencil with an eraser.
My contacts had some sort of varnish that was dry and hard.
use the contact cleaner or something that want leave a film to clean out the grit.Re-assemble the switch with just the #4torx first to verify you got it back together correctly. Re do your test. If it is correct you can button it down
per mentally.

 

Nice write up.