Here is a discussion thread from a while back on the ZL1:
http://www.camaro5.com/forums/showthread.php?t=128404
The story I always heard about the price on the ZL1 was that there was an accounting change between the time Piggins told Gibbs what the price would be and the time the cars were delivered. Something to the effect of Piggins was going to use R&D budget to build the ZL1s and then sell them at whatever it cost to make them, but the bean counters or someone on high decreed that development costs had to be rolled into the prices charged for this kind of project. The Zl1 engine ended up doubling the cost of a new Corvette let alone the Camaro.
50 Zl1s were ordered by Gibbs, 19 by other dealers. Some were taken back by Chevrolet and redistributed to other dealerships. Some cars had the engines removed and were sold with other engines.