Stu, you really are a treasure trove of amazing information! Thanks!Zat actually owns some remnants of a second 164 procar that was never finished.
As to the Alfa/Ligier, there was another motor. It was built by Alfa FOR Ligier, but never raced. It was a 4 cylinder 1.5 liter turbo, similar to what Brabham was using (but made by BMW). The motor was actually at Alfa Ricambi in the showroom about 10 years ago, when they were still in Glendale, California. I don't think Brad owned it, and it was just leant to Ricambi by Alfa...