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This page shows the most common vacuum line diagrams for stock TPI setups:

The diagram above is for 1985-1989 F-body (Camaro/Firebird) MAF TPI

This diagram is for 1990-92 F-body (Camaro/Firebird) Speed density TPI

The diagram above is for 1985-89 Y-body (Corvette) MAF system.

Above picture shows some of the various vacuum lines and fittings you'll need to complete your set up. This is not all of them, but gives a good idea what may have to be done, especially if you decide to use anything but the stock valve covers.