Yes, upper intake or "plenum" has to come off to get to it. The pipe on mine was rusted out and the valve was shot, I did the eliminator too... Just bent the pipe back on itself and crimped to seal.

took it in for inspection thinking pep-boys mechanics wouldn't look too closley as long as I passed the dyno. WRONG. passed the dyno sniffer fine but failed and got a speech about how my emissions system has been tampered with.

So now I get to either replace it all or make it look like the old valve is doing it's job.