I had a set on my 72 K20 for 20 years, had to clearance one of the exhaust flanges to clear the rear shackle, think it was the passenger side but cant remember for sure. Passenger side does hang down further than the driver side but a good exhaust guy can get the pipe up over to the transfer case.
Good pic of a set here:
http://67-72chevytrucks.com/vboard/s...horley+headers
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