With the applique still on the transfer paper, I carefully cut out both noses and swapped them out. I also decided to swap out the eyeballs. The indentations on the transfer paper made re-aligning them easy.
Since I had the pencil line for the window opening, I left the bottom edge of the protective paper in place on the back side of the acrylic to help line up where Stimpy should be standing. I placed a straight edge along the line, and tore the paper along the bottom as I removed it. Per the applique instructions, I washed the panel and then applied my modified sticker.