Keep the rearend still
 

I'm looking for a side to side brace for the rear end on a leaf spring set up. Something that keeps the wheels on the rear end from coming out under hard corning. The rear can pitch out a bit and I want something similar to a watts linkage to keep the rear-end in check. Does anyone know of any company that makes something like this for the first gen?

use the Derlin bushings
 

on the leafs from Global West. That should solve your problem

the spring will still twist a little, he's looking for something like a bolt in panhard kit. I don't have experience with them, but people like david pozzi etc have said that it is something you want to be carefull with because if not done correctly it can easily cause bind in the rear suspension, specifically on leaf spring cars

If your tires are rubbing a little it is probably due to them cambering in a little, putting a panhard etc is not the correct solution to fixing the problem. Wheel size is. However if it was me I would start with the del-a-lums like suggested. that will get you in the right direction. I have them in my car. Using them in the front spring eye pocket does make the ride a little harsher but nothing huge. Also if you are running a rear sway bar you will probably want to ditch it if you go with the del-a-lums

Yes, exactly I was looking for a panhard style system. I was wondering if there was a high quality kit available for this car? Yeah, I figured it should be done correctly and be a good kit to not bind up. Anyone?

I'd do the del-a-lum's first, of course unless you just want the panhard for the "go-fast look". How much movement are we talking here? Have you rolled the fender lips yet?

http://fays2.net/

Is this what you are looking for?

Yeah we shaved the fenders enough, but in hard corning I can feel the rear step out maybe 5/8's of an inch or so, way to much for my taste. That FAYS2 looks like that's the ticket. This works with leafs?
It also looks like it's for mustangs only.
Thanks again guys

How does one feel this while driving?? What is your current setup? something sounds weird. you can't, well you wouldn't want to go start slapping on suspension pieces that could compromise its performance without througly thinking it out

Well I used to race cars and I know the "feel of my pants" driving pretty well, and can tell when a car is not doing something it should. I can outright feel the rear end move this small of an amount. Yes you're right, I won't be putting on parts for effect, but I do drive the car aggressively, and can tell when something doesn't feel right. The rear setup is Comp engineering slide a links with Global west leafs with duel adjustable QA1's in the back with a sway bar, which is being replaced with a different kind with more adjustability.

Well if I remember those slide-a-links already have solid front bushings. I would still do the rear with the del-a-lums, they are a superior bushing and will also help with lateral deflection. I'm still suprised its moving that mucy, are you sure the feeling you are getting isn't from some kind of odd slid-a-link setting? Too much preload? I would think the rear swaybar would help some, since it would resist bodyroll= less pivoting/less axle side movement

EDIT: also do you still have the rubber bushings between the axle and leaf spring. I would be getting rid of those too.