There are many problems with this because of Torque.
There is no variable that you can just type in and suddenly you don't collide with players.
You cannot remove the collision box at all.
You cannot make it really small or else you'll be falling through bricks and everything else.
You CAN use a hacky script in order to make the player go through a different one. Trigun has done this, however, there were several faults with it that can't really be fixed.