So I removed my n64 power switch, and my goal is to hook it up to a light switch and put it onto my case (make a briefcase N64.) Anybody know how i would accomplish this?

It's unlikely. I think that light switches are SPST switches, whereas the N64 is a Quad Pole Single Throw.

What if you use a regulator like you would on a portable?

you can use transistors, but I'm too lazy to draw a diagram and tell you what transistors to use or you can just put the switch before the regulator

-Frenchfries

Ok, if I can't wire up a light switch, what's the best way of going about making a quick-n-dirty power switch. just simple power switch/button for n64

Derp I wasn't thinking.
Basically, you bridge certain pins so that the N64 stays on constantly, then put a light switch on the power source.
I'm too lazy to find the details ATM.

Bridge pins 1 and 2, 3 and 4, 5 and 6, 7 and 8. Hook up the switch to the power source (batteries or wall power) and put the regulator after the switch then hook up the 3.3v line to the 3.3v line and the 12v line to the 12v line.

-Frenchfries