Forcing HEVC MP4 to use 8 bit instead of 10

I am trying to get MCEBuddy to encode the HEVC MP4 files with 8 bit instead of 10 bit as the 10 bit does not play nicely with some of my firesticks. I don’t really understand handbrake which is why I use MCEBuddy. I am a GUI guy. So any help with how to change the arguments for this to encode with 8 bit would be greatly appreciated. I understand that I will need to make a change to the profiles.conf file but I am not sure what parameter to change.