I left everything visibly intact on my '77 T/A with the W72 400. All that was done to disable the EGR is to place a bee bee in the vacuum hose to the valve. That way it appears hooked up and functioning, but no exhaust gas to enter the intake mixture.
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1976 LeMans B09 Freeway Enforcer, 455/M40 Smokey
1977 Trans Am, 400/M21 Black/Gold Bandit. 44K actual miles
2017 Sierra SLT 1500 Z71 4X4
2019 Canyon SLT Crew 4X4
