Automate the task of selecting and deleting some pixels relative to layer dimensions

I take numerous application screenshots and paste them as layers in PS. How to automate the task of selecting and deleting relative pixels for each layer. For example, I want to delete (layerN.width,1 ),( layerN.width-1,2) pixels. So the flow would be:

1. Take alt+prtscr screenshot
2. Paste as new layer
3. Automate the task of deleting as described bellow.

I want to automate the third step only. Currently I am selecting pixels by hand which is tedious. Thanks.