Bare metal install - need Atheros 9K wifi driver

I’m trying to get started installing RancherOS on a spare laptop with a Qualcomm/Atheros 9K wifi card, but I haven’t been able to load the ath9k driver from the rancherOS kernel source that I built and tried to copy in. I can’t enable and start the kernel-extras service because without the wifi driver I don’t have basic connectivity. I’ve read through the docs for building a custom RancherOS ISO but I don’t get where I’m supposed to start- ideally I’d like to have an ISO with the ath9k wifi drivers and dependencies built in and I can go from there. Also there’s no ‘depmod’ on the v1.5.4 rOS system I installed on the hardware (??). Can anyone get me pointed in the right direction? Thanks!