68 340 Vibrating idle, loss of power

If it revved like hell when the throttle stuck, it is not uncommon to punch a hole in a rocker, or bend a pushrod.
You may want to check your rocker arm functions, you mentioned a ticking .
I couldn't get throttle at that time as the screw on the linkage was sticking on that carb and not opening. I set the valve lash up for the cam spec and that moment I didn't have anymore ticks. Now I'm hearing everything, along with vibrating and shaking and definitely feel the loss of power