Can you get some pictures of the pulley Pooh Man? I'm thinking there might already be ones made for other ecotec engines that will fit.

Here is one possibility:

5 ribs - Ecotec Lightweight Crank Pulley - 2.0LNF/2.2/2.4: by Make and Model - Chevrolet - Cavalier - 5 ribs Ecotec Lightweight Crank - Car Performance Parts And Auto Accessories | MRZ Performance

Here is a comparison pic of the stock vs MRZ underdrive pulley: