Sorry I didn't see this post earlier. I've got a couple suggestions, hopefully I'm not too late. All of my suggestions just involve labor. One suggestion is to try to lower the roll center but that's only if the front suspension geometry is the same as the early Vega. I'm not totally sure if it is.
Measure the distance between the upper control arm (UCA) pivot and the lower control arm (LCA) pivot. If it's less than 9" between them then this modification is worthwhile. It does require a tapered reemer that matches the BJ taper. I think it's 1.5"/ft. I actually borrowed one from a shop down the street. (anybody else that knows feel free to chime in here). They are not inexpensive but you could probably sell it when you're done. I think the rules only cover actually parts into the bottomline. This would be a tool purchase... The mod is to burry the BJs about .5" into the spindle mounts. You still have clearance, although tight, but more importantly you reduce the height of the spindle (UBJ pivot to LBJ pivot about 10"). This moves the rotation center out and therefore the roll center down.
Why is that important? Then you can absorb the roll through the springs/shocks/swaybar and not through the suspension components. A roll center that's too high will cause more skidding because the roll force is applied high. It's like pushing a heavy box across a floor. Pushing the box low moves it smoothly. Pushing it high causes the box to catch and move inconsistently. You can't really get the roll center too low with our cars. The built in suspension geometry will not allow it but the lower you get it the better.
Another mod is to lower the CG by lowering the car. There are two ways to do this inexpensively: Cut the springs, and make the front spring pocket deeper. Cutting the springs is pretty easy. I took 1 whole coil out of my front and rear springs in the Vega before going with coil overs. For the fronts cut one coil out, heat up the new top coil and flatten it out. I know what you're thinking but it won't ruin the spring at all. In fact cutting an old spring will yield a very stable spring. Just make sure you let the coil cool down slowly. Here's a couple pix:
This does two things. It lowers the car a bit and it increases the spring rate. For my '73 Vega, cutting one coil out lowered the car about 1.25" and brought the rate up to 430 lb/in. This also flattens out the LCA to yield more favorable neg. camber gain.
In the rear cut 1.5 coils out. This will bring the rate up to about 175 lb/in. and reduce the height to more like 1.7". Then adjust the ride height in the front to match the rear or a bit lower with the next mod: Make the front spring pocket deeper. You do this by cutting the bottom of the spring perch in a slight spiral. Then bend a piece of sheet metal to match the dia. in a similar spiral. That adds depth to the pocket while keeping the index of the lower perch for the spring coil and the shock mount. Here's a couple pix. One note here, these pix are of my LCAs. I needed the pockets to be a LOT deeper. You may only need 1/2" or so. Just lower it enough to make the front a tiny bit lower for high speed stability.
Fat sway bars if you can afford them. Leave the rear small dia. for better handling. Fat as you can get in the front. Lowering the front will yield a little bit better caster. If you're using S10 ball joints, weld the sleeves in the lowers move toward the front. That should help a little. Then you can mount the upper a little rearward.
Get rid of the front bumper if you can. Cheap posi?