Home Assistant Yellow - External Wifi Antenna Setup

I’m trying to edit the firmware config that would allow for connecting an external antenna to the CM4 in my home assistant yellow. I tried following suggestions here and installed HASSOS SSH setup add on which did allow me to tunnel into my device but I wasn’t able to access the config files needed to change the antenna. Could anyone point me in the right direction as to how to access the boot config files either through SSH or other means? (/boot/firmware/config.txt)