Regarding the DD tail.

Well I've looked at and studied this for two days now and only one thing will make this work.

The "leading edge of the rotor must rotate up towards the main rotor" thing can't matter. If it does, this set-up will not work.

The pic of the DD tail on the Blade cp repair site clearly shows that with the prop oriented the way it is, it will have to spin leading egde down, away from the main rotor in order to properly move the tail to the left. (as viewed tail toward you)

If this is OK then you don't have to flip the motor mount or reverse the wiring, just put the rotor on the shaft and your done.
If this is not OK then you will need a prop that has the reversed pitch.

The stock rotor propels air from left to right with the tail toward you. It does this with it's leading edge moving up toward the main rotor.

The blades on the new rotor are opposite the stock so for it to propel air from left to right like the stock one, it has to spin in the opposite direction which would be leading edge down away from the main rotor.

So, either some people have found the correct pitch blade or the spin direction doesn't matter as long as it's propelling air from left to right (tail toward you)