My left rear blinker is not working and I think it's due to the switch in my column going bad. Would this also make my left rear break light not work to? I followed it all the way back to the steering column. I'm hoping once I change it out they'll work again.

I know my tail light is grounded because I pluged all the right hand side bulbs into the tail light and it blinks fine. I've heard of people having one side working(blinking) and not the other from a bad switch before, I think .

It's a 1969 bee if it help with the wiring I'm talking about. I followed the dark green wire back because it controlls the brake and blinker to the left rear tail light and it's not getting any power all the way back to the column. So I'd assume it's the switch in the column that not getting a good conection for the left side rear blinker to work.

"How hard is it to change a turn signal switch?"

Not too hard, if you have a steering wheel puller and are comfortable doing things of this nature.

The bit about no power on the shared wire would have helped at the outset.

The power to the brake lights does in fact pass through the TSS. The switch opens the brake light circuit on the side to which you signal, substituting instead power supplied through the flasher. This is how one side is on solid and the other side blinks as you brake while signaling. It sounds like you have done a bit of diagnosis before posting, and that something is amiss in the area of the column. It could be a connector or broken wire after the switch.

I would recommend digging into the column (but not necessarily buying a new TSS yet) to continue your diagnosis.