The Bell Labs 370 port was different, it was based on running inside of TSS/370, which was an IBM OS which hardly anyone besides Bells's ESS group used.
It's funny, I did not learn of it until after CMU discommomission that IBM/TSS system which I broke in on.
Clem can tell us all about the IBM/Locus port to the 370.
Yeah it was called and would be a product Locus did for IBM (AIX/370) primarily for the University market. It's what the Locus (TCF) book describes.
And maybe there was another IBM port??
I'm not sure what Amdahl had originally. I had always thought it was based on your original from Princeton.
Much later, Sun ported Solaris to the Hitachi HDS 370 clones (for Hitachi), and then to Amdahl clones for Amdahl/Fujitsu.
I heard that had been done, but never knew how well it worked.