You really shouldn't have to use a track bar with leafs. If the track bar is not adjustable, with its fixed length, you may be putting the suspension into a bind with its own weight. The track bar is required for locating the axle centered under the frame. Its required with a link suspension. For the front application, its required with a link suspension and a fixed steering box due to the push/pull of the effects of the steering. For the rear application, its required due to the forces created by movement of the axle up/down. Many link suspensions triangulate the links to help reduce the requirement of the track bar at either end. In the rear application, this is done quite often but the room for triangulation of the links is what makes it happen. For the front application with fixed steering box, even triangulating the links won't have complete minimization on the effects wrt to the steering forces as well as the axle movement up/down.
For having death wobble with a leaf suspension, I'd take a look at the lug nuts, unit bearing bolts, unit bearing itself, tie rod ends, ball joints, what was mentioned above with proper torque techniques of the components, and the frame/steering box itself. Add in the steering shaft and its frame mount as well. If all that appears to be in fine order, take it to an alignment shop and request a look-see if its in acceptable alignment. (That might cost 30-$40 and if you want them to alignment more.) Also have them see if the front tires are balanced.
With all this investigating, take a look at your caliper and brake pads since everything is out of the way.....LOL.