Is it feasible? I imagine they just use i2c, if they don't use parallel communication. I have some wires I can cut up, so that's not a problem.
I understand the NXT devices do use I2C, but not the earlier RCX ones.
Lots of references and resources to be found.
If you have bluetooth on your computer, you can use Jorge Cardoso NXTcomm library for Processing.
Via processing you can, i think send data to the arduino via a Serial link.
It's a bit complicated but if you want to read the four sensors and makes the 2 motors works, it could be usefull and without any wire.