Doing research on changes to the front suspension on the Packard when suddenly the light bulb in my brain turned on with regard to the Hercules front end troubles. While installing the Watts link helped, there was still some bump steer - I've been chasing small amounts of play in various components, thinking that was the problem - NOT!! My original Panhard bar mounting was
backwards, with the frame mount on the right side and the axle mount on the left - it should be mounted to the frame near the pitman arm on the steering box, with the axle mount on the right. Then the drag link and Panhard bar move in similar arcs, eliminating bumpsteer. I've done two other cars with a similar air bagged solid axle and hairpins with a Panhard bar and they tracked fine - by pure fluke, I had mounted the Panhards the right way and didn't even know it ....
Pics tomorrow of design #3