340 Intake Manifold Heat Shield

Why remove the heat shield in the first place? The nipples, cut it off and leave about 1/16 " or more. I then cut the nipple down through the center until I knew that I was close to the threads. Then I took a small chisel and started tapping the edge of the cut I made, until it separates the nipple from the manifold or caves it in. I had it out in 5 minutes.