Turn signal snap back broken

Hello, I have a 96 TS with a semi-broken turn signal. The auto-snap back works for right turns, but not left turns. I thought it might be a burned out turn signal light, so I replaced the one on the driver's side front, which didn't change anything. I then noticed that the top 2 bulbs on each of the rear brake lights/turn signals were burned out. These are the two small bulbs. When I replaced one of these with a new bulb, it wouldn't work. I'm wondering if the burned out bulbs could be affecting the turn signal, and also why all of these rear top bulbs are burned out. I'm skeptical that the bulbs are affecting the signal, since they are burned out on the right side and the right turn signal will auto return. Any ideas of what's going on here? I checked the fuses and they're all OK.

The snap action auto hold or auto return is purely mechanical and depends on plastic tabs....

The snap action auto hold or auto return is purely mechanical and depends on plastic tabs....
Do you know how to fix it? Is there spare parts available to resonable prices?

Do you know how to fix it? Is there spare parts available to resonable prices?

Plastic parts, and some spings prone to metal fatigue and failure. Less than $3 at O'Reillys.
As for the instructions: http://www.thingsthatgo.ca/forum/viewtopic.php?f=11&p=189