Okay, so I officially switched to a Pi zero. Lots of reasons but the main one is with the gigantor battery, there isn't enough room for a pi 3. I maybe could de-solder the majority of the parts and fit it that way but for 40 dollars, I'd rather not have to buy a new one. A Pi zero however is about 15 bucks once you factor in shipping. Dropping the ability to do N64 and probably the PS1 as well, but it runs everything else before that all right. For a portable, that's pretty cool. Got a lot of work done today and last night. We got case mods, basic parts layout, power systems, and buttons. 

I mounted the PowerBoost 1000c inside a gameboy game from when I had a gameboy as a kid (TMNT). It probably still worked but I don't have that style of gameboy so... It gets re-purposed. The power connector to the battery (JST I think) was too thick to fit in the case normally, so the dremel and I got busy to fix that. The power switch is already glued in here, and you can see the button wires coming from behind the foam pieces to cushion the battery. 

The top of it got a redo as well to make a hole for the USB charger. Not the prettiest, but better than the other placement options. 

TMNT! I used to love that game. Tried playing it the other day. It was crap. Ah well. The buttons are pretty comfortable here ( I just held it normally and put the buttons where my fingers were) and if I don't need them they make a nice finger grip. 

Put the start select buttons back in. (those are the video power and data cables.)

I used retrogame to program the button controller, here's the config file.

The guts (mostly) laid out where they'll go. The audio amp will go in the bottom right below the controller board, and the speaker will go in that speaker hole. There's enough depth in the case that even with the battery installed, everything still fits.

That's about all for today. I can really see how this is gonna feel as a finished product, and it's coming along nicely.