hello jim.pedavoli,
please execute massfuse utility to fuse multiple Jetson devices simultaneously.
please see-also documentation, $OUT/Linux_for_Tegra/bootloader/README_Massfuse.txt
you may refer to $OUT/Linux_for_Tegra/tools/kernel_flash/README_initrd_flash.txt of [Workflow 8: Secure initrd Massflash] for more details.
just double check.. are you going to enable Jetson security with the same keys? for example, you’re using the same SBKPKC key for all your products?
besides, you may refer to similar forum topics about massfuse, such as.. Topic 273585 and Topic 222924.