What was originally used to attach the front fender extensions on a 70-2 Dart/Demon.I have the later 72 version using the threaded studs.Was a flat or lock washer used along with just a regular hex nut? Thanks for any help

Its called a pal nut, this isn't likely the correct size but it has a pic for reference

Pal nut

Are your fender extensions pot metal or a fiberglass type material? I ask because the ones on my 72 Demon were metal and the replacements I have are some sort of fiberglass/plastic stuff and I believe they are from a 70 Dart. My 72 Demon ones were just a stud and not at all threaded.

The ones on the car when I got it were part #3574116-7 (potmetal) and have the threaded studs.I bought a pair of NOS ones,#3573788-9 (potmetal) and they have the smooth,molded in studs that I assume would use the pal nut like you showed.These are also listed in the parts book as up to 12/01/71 and I also bought a pair of NOS #3574148-9 that the book shows after 12/01/71 (I have not received these yet,but will post what material they are made of) My car was late 72 production (April 72) so according to the book,my car should be this last number...but

If you go look at this listing you can see the nuts that the non threaded stud use. I don’t have any information on the threaded ones sorry.

Look at this on eBay

MoPar 70 71 Dodge Dart Demon Fender Extensions With Chrome 1970 1971 1972

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F123892192534

I’ve been looking for quite some time for the fiberglass extensions which is 1970 only. In ‘71 they were pot metal with molded in studs and ‘72 they were pot metal with removable studs.

My 1972 Demon has a build date of 9/71 Sept 1971 it has the metal fender extensions with moulded in studs.