Those AMA weights, although the starting weight seems a little suspect, they all end up being closer to reality than we might suspect, as stated above. I found a road test of a '67 Fury III convertible with a stated curb weight of 4280 and a test weight of 4660. When I added the option weight additions for the '69, it came out to be 4365lbs (383-4bbl, TF, PS, PB, PW, radio, undercoat).
KEY thing is that there are several "weight" specs. Shipping weight at the end of the assembly line might be the most reliable and constant amount model years and such. As mentioned, finding a set of scales, a HellCat (in whichever body it might be in, which IS variable!!!), and your car, would certain see which way the money changed hands.
Remember, the HellCat HEMI might have started out in Challengers and Chargers, but have expanded to almost every Chrysler/Dodge rwd car/suv platform! Given its LX platform, the Challenger is a pretty heavy car . . . even heavier than many C-bodies!
CBODY67