Holley efi and nag1 transmission

Pretty sure that would be a big no. I think the TCM uses input from the PCM and the Holley won't talk to it.

Hotwire Auto has a tech article on getting a NAG1 wired up and it includes an ABS module, speed sensor, FCM, shifter and TCM, besides the PCM.

https://www.hotwireauto.com/nag-1-swaps
There is a standalone option much like for the 8HP, from the same guy.

https://www.soundgermanautomotive.com/pcs/
That would probably be your best bet for running a NAG1 with the Holley PCM.