LEVEL CONTROL PARTS UPDATE:
Thanks to all who were interested in and who helped me with this idea of starting up a business reproducing parts for GM Level Control compressors.
It looks, after a lot of hard work and time, as though it's not to be. High tooling prices and piece prices, as well as lack of demand, combined to make it impossible to make a profit, let alone break even, on this idea.
Again, thanks to all who inquired, and sorry to disappoint.