Not sure of the bump-steer problems you will encounter with the Cavalier r&p, but would think they would be substantial. Here's a glimpse of the geometry needed....
http://alcor.concordia.ca/~istih/fig-11.gif
You might consider using a front clip from an S10. The track is close to the same. It would give you a modern IFS, r&p steering and disc brakes.

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