Originally posted by Cowboy from Hell:
Panteramerica was California based and owned by Barry Gale and Steve Hitter, they were possibly the earliest gray market importers of Panteras.
Alloy Boss 351s were not available as assembled engines as far as I know, but the alloy Cleveland blocks and heads were manufactured for Can Am racing. Dyno Don Nicholson has always been rumored to have ended up with most of the alloy 351C blocks & heads, he used them in his match racing cars. Gary Hall got his hands on some of that stuff eventually, there are a few Panteras out there with alloy Clevelands courtesy of Hall Panteras. I have a friend with a couple of unused pairs of the heads.
Kelly Coffield & Dan Jones have addictions to Ford alloy parts and surely have more info.
I've never had my hands on an alloy SK block. They are rare items and had some extra head bolt provisions among other intesting things. Dan knows of one that had lifter gallery damage and repair. Here's a few pics. I don't think it is available for sale but you'd need to ask Dan.