Using a potentiometer attached to a plastic sprocket, we could determine the orientation of the modules on our swerve system to within 1/255 of a rotation (except around the couple degrees where the potentiometer recycled). There's little to no need for visual cues of module orientation if two things: a) you can control direction electronically, and b) your driver is good enough.
If you want a feedback system like this, I suggest you first find someone familiar with PBASIC enough to attempt writing the code for you, if you don't think you're up to it (I seem to recall a couple threads in which you asked for programming help).
If you need any more intensive help, feel free to ask. I'm willing to explain most of our system (only "most" because I don't know the software algorithm used to
actually steer). Mechanical and electrical aspects of it, though, I am very familiar with.
Oh,
here's a picture of one side of our swerve. You can see the black plastic sprocket on the right, next to the drive module sprocket.