well man, i highley DONT suggest putting it into a go cart, restore it to a big red, by the way, ALL 3 wheelers had stopped being made in 1987, no offence or anything, your a newbie, but just so you know, i have never owned a big red, nor do i know its electronics, but, look at your engine, there should be a wiring harness coming out of it, maybe 4 wires, take a test light and test the wires, the one with the most power (produces most light) is most likely your lights (i think) and the next one goes to your coil, which provides a spark, make sure your carb is set right, and all, then your ready to go!
Hope this helps
Curtis
Currently Trikeless- but I have a LT250R