I need a little help/advice

Check your data tag.

If it shows B43, it was ordered with disc..
If B41 shows, it will be power disc


http://www.hamtramck-historical.com/images/dealerships/DealershipDataBook/1973/73_Dart0019.jpg


They used SBP drum front brakes all the way up to Jan.1, 1976

http://www.hamtramck-historical.com...rshipDataBook/1976/76-Valiant-Duster_0015.jpg