Thanks for the help so far guys, i didn't get to try this today, i was just too busy at work to get any time to mess with it. here is my progress so far:
I started by gutting the dead snes in question. It was severely discolored. the top was very yellow, the bottom was yellow really bad on the front and right side. I left the pieces sit in a mixture of hydrogen peroxide and oxy clean in a clear plastic container in the sun for about 3 days. It did improve the color, but it didn't get rid of the yellowing completely.
I'm most disapointed with the purple buttons. When i got it, they were very dark and discolored. by soaking them, they brightened up, but once they dried, they are cloudy and washed out looking.
here you can see the buttons, and the bottom side of the button, showing the original color.
here it is after soaking for 3 days. perhaps if i had a stronger mixture of peroxide i could get it back to normal, but i couldn't find any locally.
it is hard to tell by that picture becuase the buttons are wet, but once they dried, they are splotchy and nasty looking. i don't see any option but to paint this unit.
i really like the original color of the purple buttons, and i found some rustoleum spray paint that bonds to plastic, that just happens to match almost perfectly.
i also got some Charcoal duplicolor vinyl dye to paint the main part of the console...i just like the darker color, more like the n64. I'm not sure if I'm going to keep the eject button, or if im going to replace it with a piece of steel mesh painted a medium grey.
i'm hoping to get it painted this weekend.
i did start working on the back panel for the connectors. I don't want to put any extra holes in the case. I removed the original back panel from the PCB and cut off the power jack. I have an hdmi extension that fits pretty well into the original hole for the nintendo AV connector. I made a spot for a USB extension in case i need to hook up a keyboard or something, and a USB type B jack that will be the power input, which will plug into a standard cell phone charger. i just cut this jack off of a PCB from a non functional external hard drive enclosure. the ground pin will connect to a cut off micro usb cable running to the raspberry pi, and the 5v pin will connect to the original snes power switch, and then to the micro cable. This will allow me to cut power to the unit. (I always shut down from the retropie menu before turning the power off...I just don't want to spend any extra money on this right now to get one of those mausberry things)
original panel after taking my pocket knife to it...the holes arent perfect, but they are close enough.
here it is with the connectors loosely fitted into place...once it is painted, they will be stuck in place with hot glue.
that's about all i have for now.