So, the important info on the VIN is
1st digit- L (Dodge)
3rd & 4th digit- 29 (2 door sports hardtop)
6th digit- 1 or 2 (year code, has to be '71 or '72 to be a Demon)
First digit as an "L" tells you it is in fact a Dodge, or in other words, not a Duster converted to be a Demon. 3rd and 4th should be really obvious, it's a sport body. But if your VIN is swapped or something who knows. 6th digit is also important, to rule out a later Dodge Dart Sport cloned over to be a Demon.
Full breakdown is here
Mopar VIN Decoding
Tail lights and bodywork can be deceiving! Lots of later model Dusters and Dart Sports masquerading as Demons these days :p
My '74 Duster turned into a '71 Demon tribute...
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