Thanks, Scott, appreciate the kind words. The tint on the alternator shells in the pictures is from a weak chromate wash. I have seen this on many assembly line pieces and most NOS shelf stock. If you look inside most 66 - 71 alternator and starter housings, you'll find traces of it. Apparently, it didn't weather well and was a short term solution to oxidation on aluminum parts after casting. Most NOS alternators show not only a chromate wash on the shells but also on the clear zink hardware. After talking to some plating guys I trust they pointed me toward a chemical that replicates the finish. As far as the orange marking on the rear shell, it is an indicator of amperage. Unless you specified an amperage upgrade when ordering the car from the dealer, CC supplied you with a 37 amp alternator on most "muscle cars."