So here’s what I did. I changed the throttle lever to one with a reverser lever on it. Mapped the lever to “hold throttle reverse thrust” and set the button to ‘on press’.
Mapped increase throttle to detent of Prop lever and set that one to ‘on release’.
Mapped decrease throttle to detent of throttle and also set that one to ‘on release’.
All other axis’s are as in the video.
So how it works. Push Prop lever down once and return to set low idle. Once more to high idle. Increase mixture to full will set lever to throttle. Use throttle as normal and pull reverser when you want to reverse. In the video it put you in full reverse. This way gives you a bit more control over your reverse speed.
When powering down. Set throttle to 0%. Decrease mixture to 0 and hit throttle detent once to move to low idle, again for cut-off.
Just be careful not to bounce the detents or it doesn’t work right. After about 10 times doing it I have it down 100%.
EDIT: Did one change after I posted this. I bound Prop and Mixture to the same axis to minimize the amount of moving parts 
Works perfect.