Turning a 74 into a 72

I know the "quarter extensions" are different but they just bolt on and the marker lights are different on 70's but the "quarters" being different? Not to sure about What you mean that the quarters are different....

And keep up the good work, I'm starting the same project on saturday!

You're right about the extensions. The 72-73 quarters and the 74-76 quarters have the same side markers but they are in different locations. 72-73 are in the same spot as the 70-71 but on the 74-76 they are higher and more to the front.