Disc Brake info!

Well, I'm pretty new to working with brakes, but in removing my front suspension components to rebuild them, of course the brakes need attention as well. The car is a 68 dodge dart, it had the front end "upgraded" how ever long ago, and the person I bought the car from wasn't sure what the donor car was. Now I believe the brakes are Chrysler single piston calipers, with 11" brakes. other than that I dont know much about brakes. Seeing I'm rebuilding the front end here are my questions.

1)Does anyone know what time period these brakes are from? Year wise
2)What is the bolt pattern?
3) Also, should I rebuild the calipers? or just buy new ones?
4) I believe I read somewhere that the discs should get machined, is that something I should do?