I am bummed to hear this news as well. I thought Schwartz made a nice project: we used the front 2/3 of one of Schwartz' chassis for Murray Pfaff's 1959 Imperial Speedster:
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The back 1/3 was custom, as it runs a narrowed Viper IRS. However, this was a scratch built car and the chassis was not made to fit it. Therefore, we could not access if the Schwartz Chassis was a true bolt in.
On a positive note, Murray has over 7k miles on the car without a chassis issue. The car drives and rides very well. I think you will really like your Chevelle when it is back on the road!