I ended up with this pcm (see pics) running a fairly new big block. year model 2017.
The very limited info I could find about this pcm seems it was also used on some GM crate engines etc.
I am hoping to make an information thread. As well as a bench harness to read it "hopefully"
Feel free to add info if you know anything about these pcms.
Thanks
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I tried this setup with no luck
J1-19=battery pos
J1-20=battery pos
J1-43=can low
J1-29=can high
J2-13=switched 12v+
J2-28=switched 12v+
J2-73= gnd