I made a custom cart as a personal project but want it in a repro cart shell instead of just bare PCBs, which means a cutout in the shell to expose a USB port/card slot/other things. The plan is a rectangular cutout marked in the photo. Any advice on how to do a reasonably clean job without too much hassle? Or a recommended Dremel bit to make it easier? I haven't worked on this type of plastic before and was told it's not that easy to work with. Can't find the thread about it again but apparently it's why some AES Multi flashcarts have pretty rough looking cutouts for the SD card slot and it caused a few complaints. They might've used the same type of repro shell. Asking for some advice before wrecking a shell and having to order another. Being careful with drill speed and heat to avoid melting the plastic is one thing I remember.