Looking at the "collective" I am assuming it is a fixed pitch heli? And your knob that you call the collective is a throttle perhaps?
If that is true then good luck, my model helis were a pain to fly as a fixed pitch machine, there was a noticable delay between inputting power and the aircraft gaining altitude. The normal point for noticing this is when descending too fast and needing to stop the descent and praying it reacts in time.
I'm being anal here but you don't have a Fenestron, a fenstron is what is on a dauphan/ec155 etc, the tail blades enclosed in the tail fuselage. You have a normal tail rotor but I don't know if it has a specific name.
Good luck and be carefull, but we want a video of the outcome good OR bad.
Si