RE: challenger of an unkown year
Do you have side markers that are inset in the fenders and quarter panels (70-71 years) or do they stick out of the fenders(72-74 years)? What does your tail lights look like? This will determin 70 or 71 year. 72-74 all had the same tail lights. If you had pictures it would be easy for me to tell, but if you can describe it I can tell also.