Like the others have stated, it is NOT possible (at least not without great effort) to modify an existing Walbro carb for use with the solenoid.
What you need, is an equivalent to your current carb Stihl M-tronic carb, or one at least compatible to your engine.
Since Stihl uses a different bolt pattern from Walbro, you will need to do some modding here and there.
But once fitted, indeed the electronics as discussed in this thread and the RCGroups thread, should be fully able to do the job for an engine in airplane configuration.
Mind you, you still need a TX with good curve programming functions, and you still need to determine those curves yourself.