Along with the info previously referenced (some of this is redundant):
The differences between a RS and the standard body included (in 1969):
different outer fenders, different inner fenders, different grille, hideaway headlights (based on vacuum actuated, articulating, headlight mounting bracket to rotate the headlight covers in and back in the open position), inner and outer headlight door covers, vacuum cannisters, mounting brackets for the vacuum cannisters, vacuum reservoir, relay valve and the associated vacuum lines, different headlight switch with vacuum hose connections, different windshield wiper switch (2 dentent positions, first detent routes water to the windshield washer nozzles, second detent routes water to the headlight washer nozzles which spray water on the headlights), headlight washer nozzles, diverter valve on the windshield washer pump, water tubing from the diverter valve to the headlight washers, and even a difference in the front header panel to accomodate the headlight washers themselves --- even down to the miniscule items like the bracket that holds the windshield washer bottle - it is in a different location on a RS. And this doesn't include the Style Trim RPO Z21 items that are a part of RPO Z22, the RS package.