1973-DUSTER-Oregon.

awesome job! thank you for sharing those photos. most people always run the exhaust on the outside of the spring I have wondered if it would fit along the inside like yours. looks good. I assume there is no issues with the springs hitting? also I don't know if I missed it but whats the diameter of your pipes?
The pipes are 2 1/2 some places are real close but will clear. If a person had softer springs it might be a problem.