I want to convert my rear brakes to disc mainly for simplicity and I absolutely freaking hate drums. Can I just go to the junkyard and pull the front knuckle off a Neon and put it in place of my rear ones?

I don't recall the fronts being the same as the rears? Get the rear knuckles. This is the parts list I found:

-Rotor
-Pads
-Caliper + Bolts
-Caliper Adapter
-Hub Assy
-Brake Lines
-E-Brake Cables

Some ppl have said they found the whole thing on Craigslist for $100. The other option is to get the knuckles from another car, and then just buy the other parts new. That's personally what I'd do.

I'm in the process of doing the conversion o mine and just possibly found another R/T parts car. If i get the car I will let you know, should have everything you need

E-brake cables are among the list....if the original is used, it will not brake the emergency brakes, right? Thats why the donor cable is transferred, right?

I am not positive on this answer as that is only a list that I found, not created. I'd venture to imagine that the parking brake cable is different for drums than it is for calipers. Therefore, if you have calipers, you need the cable made for them.