How to disable RIL on Android?

As soon as I connect a USB modem to Android device, the system grabs ttyACM0 and ttyACM1 in an attempt to open connection. As a result, the ports are blocked and can not be opened by other services. I have tried making the following changes in init.rc, as well as deleting ril-deamon service entry. setprop ro.radio.noril yes setprop hw.nophone true How, if possible, can I disable RIL on Android to avoid having it block ttyACM0 and ttyACM1 as soon as modem is plugged in? Is it doable without having to rebuild Android?