1970's Hurst "Just-a-Link" A-body traction bars
 

Does anyone remember these or have a pic? They were a bar that connected the lower control arm (rear sway bar bolt) to the 12 bolt housing to prevent wheel hop.

Lee, YOU are the man, thanks! Was beginning to think I just imagined having these on my Chevelle back in the day lol! They really did work so well....I tried the ladder bars, No-hops and finally settled on these.

How did those mount?

very simple, one bolt is the rear one on the lower control arm (if factory equipped with sway bar) and the other end the bushing/bolt connects on an existing bolt hole on the plate that holds the rubber snubber.

Well, that certainly would tend to lock up rear axle travel, wouldn't it! Creating a triangle there with fixed length on all 3 sides should be pretty darn stiff!