I did some research on it using the original sales brochures, old photos of untouched cars, etc. It appears that 70 & 71 used the triad on flat hoods. 72-74 used the Dodge letters on the flat hoods. 70 & 71 shaker hoods used the triad. 70 & 72-74 performance or magnum hood used the Dodge letters. 71 performance or magnum hood was without letters and R/T was available in a large decal for the front of the hood or the hood could be left blank.