I just got a Turnigy Aerodrive and I would prefer to use my Tru Turn adapter instead of the adapter included.

I tried sliding the shaft, but even with the grub screw removed it won't budge either way even with the c-clip removed. Before I force this thing, I would like some advice on the proper way to do this.

Below you can see the motor as it comes in the box and the replacement shaft.

After doing a little research, I guess I just have to tap on the shaft to get it to slide through.

What is the reasoning for having the shaft sticking out of one side vs the other or is it just random?

It sticks out of the side of the case that doesn't turn, as the other end is tapped for a bolt on prop adapter, so no use for the shaft to stick out since the whole case/bell end spins.

That bolt on prop adapter was junk. Moved the shaft to the other side and used a Tru Turn instead.