took the SC off and there is coolant inside, not a lot but not a little... any ideas how that happened or what caused it/what I should check?

bright neon green, same color as the coolant I use. if it's any consolation it didn't look oily, or like it had any other kinda fluid/oils with it.

Yikes. After the way it ran yesterday I didn't intend on driving her until I got some kind of resolution. misfiring, losing power and overheating. i was thinking changing the thermostat/gasket anyways, along with the heater exchange is really bad looking. do you think the coolant in the SC could be causing the misfire, loss of power and overheating?

No backfire, but randomly will misfire, that usually corrects itself after a minute. but yesterday out of no where going up the parking garage, I was in 1st, pedal to the floor just putting. Going absolutely no where. it didn't feel so much like a misfire as it did some kinda loss of power. It wasn't ticking or sounding like one of the cylinders wasnt firing it just would not go. and kept jolting. Then the thermometer light came on and I turned it off immediately and had to park on a low level. I have been checking the oil regularly it looks clear and as it should.. coolant in the overflow tank looks fine no oil. 133xxx miles. Had an oil change a few months ago, new plugs/wires/coil pack/radiator hoses as of a few weeks. a week or so ago i tested for stuff in the coolant to see if I had carbon monoxide in it (or something along those lines) and it came back negative. throwing code p0301 cyl 1 misfire and now it's throwing multiple random misfire. its gets really hot and smells. Not like burning oil, or gas I can't quite pinpoint it. Someone asked if it smelled like rotten eggs, but it isn't that kind of foul smell either.