I don't have a bunch of '71 340 DEMON info but: 2 - J54 cars with TX9 UDFs in August '70 (no other J54 & TX9 cars). 1 - J54 car with 5X8 UDF in December '70 (earliest 5X8 car).
Maybe the plant had issues with fastback a-bodies w/different process with hood paint/UDF paint Dodge VS. Plymouth, and simplified it ..... paint the hood = paint the door frames.
Maybe the plant had issues with fastback a-bodies w/different process with hood paint/UDF paint Dodge VS. Plymouth, and simplified it ..... paint the hood = paint the door frames. 
