Throttle arm attachment?

[1967RS/SS]

I was cleaning up the engine compartment when the throttle arm came loose.

Looks like the pedal rod presses into the the half circle shaped hole but is there a pin or clip that secures it and prevents it from slipping out? 

Checked the AIM but didn't see anything that shows a retainer or clip of some sort...

[Mike S]

It is held in place by the clamping force from the nut and bolt

Mike

[67 RS Ragtop]

X2

[x77-69z28]

X3

[1967RS/SS]

Thanks guys