The "hey dad it's clicking" in my son's '07 HHR LT turns out to be a protruding handbrake cable whose barrel end popped out of the cantilever inside one of the the rear wheel drums.

But I'm having a hell of a time prying back the spring while trying to get the barrel back into its seat on the cantilever.

Does anyone have any clever tips / tricks to share for manipulating the barrel back into the cantilever? At this point, I haven't taken anything off but the drum, and I'd prefer not to have to mess with removing the hub or bearing.

Any clever suggestions?

 

Needle nose vise-grips.
Honestly, I haven't done this on a HHR's drum brakes since my SS has 4 wheel disc, but this should work just the same.
I've used this method on many other cars with drum brakes. Just adjust the vise-grips so you can push back or depress the spring about 3/4 of an inch. Then clamp the vise-grips down on the cable to hold the spring back while you reinsert it on the lever arm.

A little disclaimer here I've even used a pair of snips or metal cutters to do this. Just gotta make sure you don't grab onto the cable too tight and damage it.

 

Welcome to the site!
A saver method, is to back off the e brake cable under the console, and I've done it this way several times.