To make the back panel I needed a small sheet of metal, I got this from the base of an old PC case I had kicking around. I measured the gap on the back of the NES case and drew this on the metal and cut it out with a dermal. But because of the shape and it not being completely square I then needed use tin snips to cut edges to the correct angle. Now make sure that the panel fits nicely into the gap if not file the edge down to adjust the shape accordingly. I don’t have a picture without the holes in it.
For the next step you are going to need to make the hole for the HDMI port. I filed down the gap between both holes on the back of the NES case above the RF Cable Jack sticker as pictured to make one big hole. I also had to file the hole above the ac adapter sticker to fit the micro USB female adapter rubber casing through.
Next you our going to want to draw around the old port holes onto the back of the panel from the inside of the NES. Then draw around the female hdmi cable end and female micro usb end like pictured below. To remove this I drilled a couple of holes and then filed the rest out to the shape drawen on the panel and checked both my ports fit nicely into the hole.
Now you will want to glue the panel into position after you are happy it fits nicely. Im not sure if theres a better glue out there but this glue we use at work and its very strong. After this haved dried, you will want to glue around the edging of then female adapters and push into position through the NES casing and new back panel. As pictured Below.
After the glue had dried and set I then covered segru over the female adapters and the inside the back of the NES shell. After the segru has set the ports are now strong enough to come with the plugging and unplugging of cables.