Hacking Questions about Gateway 3DS downgrading and emuNAND

[SMOKE]

I'm no stranger to downgrading and other console hacking, but I am new to the 3DS scene.
I know on PS3 and PSP if you try to downgrade past what factory firmware was originally on the console, you'd end up with a brick.

I've heard recently that this may not be true for 3DS. With that said, here's the questions I have:

1. Can I downgrade my 3DS (USA NES model) to 4.5x CFW ?
2. If not, is it possible to install 4.5x on emuNAND ?

Thanks

 

[night_hawk]

You can downgrade, no matter which was the factory firmware

 

[SMOKE]

Thanks

I'm now on 4.2.0-9U