Finoke,
As kissalien has stated, all 70 Challenger sunroof cars will be coded for a vinyl roof. It was absolutely required with the sunroof. Typically, most early power sunroof Mopars received a special VON, which typically started with a letter (except 1969 Chargers). But 1970 Challengers didn't always follow that rule. I have run across several 70 sunroof Challengers that have a standard 6 digit numeric VONs, but the sunroof option is clearly denoted on the Broadcast sheets. A word of caution, I have not run across any 1970 LA built Challengers that were equipped with a sunroof. Not saying that they don't exist - just have not seen one yet. I have run across 5 LA built B-bodies that are sunroof equipped, but no E-bodies. A good look at the fender tags would probably get this mystery ironed out.
Scott.