Make an initial assessment of the extent of the corrosion to the drip pan.

In this case, the middle of the drip pan was the most corroded, and the edges closest to the in-tact metal were less rusty.

Use a wire brush to remove the most corroded metal.

In this case, the middle of the drip pan was rusted through and was the most corroded.

Use the tin snips to remove the least corroded metal.

Assessing the corrosion on your drip pan is an essential step to determine which tool(s) to use to remove the decay.