Jay,
That C30 bar you describe - what years would this bar be found? 63-6xx or 60-6xx?
I have only seen one 60-66 C10 with a swaybar. I bought a parts truck and it had a tiny 0.75” sway bar that looked original. Probably was a dealer option add on.
Look for a sway bar from a 73-87 square body truck. C10 will be 1+ 1/16” and C30 will be 1.25”. You will also find them on Suburbans too, same years.
