Driver for the Frsky gas suite

Hi, i want to develop a driver for the frsky gas suite, is a module that has two temperature sensor, uses cdi pulses for rpm counter ,kill switch function and a flow meter, it alllows you to know everthing you wanted to know about a engine, however i am confused on how to implemented it, i had seen that ardupilot now supports efi engines, that also has all this functionalities and more, but the frksky gas suite is inteded for carburated engines and dosent had the amount of information, i already read the code and the dev wiki, and i dont know if i make the lua script and use an existing efi functionality, or develop like a spare sensor.