Turn signal switch wiring on a 74

[Sniper X]

I have figured out that (possibly) the reason I am not getting brake lights is that the PO of my 74 C20 removed the turn signal switch to go try to "match it up" and never replace it! So, looking at a basic wiring diagram, it appears that the brake lights will not work if the turn signal switch is unplugged....am I right?

I have power to the brake light switch, and if I jumper the brake lights streight to power they come on but do not come on if I either jump the switch plug or just press the brake pedal. I have tested the switch and it is good.

Is the plug for the wireing harness for the turn switch inside the steering coloumn? Or is it under the dash?