Updated: I mentioned below I got a faulty model. This wasn't actually the case, you have to switch it over in the dashboard for higher video resolution support as shown in the video on this page.
Someone posted on the original XBox sub via Reddit recently of a mod where you take apart one of those cheap Wii2HDMI adapters and splice it up with an XBox cable. I just finally got around to it, but as promised, I designed a case to 3D print and house this project. Unfortunately I got one of the screwy boards that show lines and oddly the audio sounds of chipmunks. But the case fits perfectly after a few different designs.
Note: I meant for the metal piece to be flipped while making this and decided not to rewire everything. My ideal situation would have been to have that flipped, add some hot glue, slide it into the housing and superglue the sliced up rubber-ish cord casing onto the end. Of course things didn't go as planned but everything should line up perfectly. Enjoy.