I totaled out my 2002 Cavalier and I'm swapping the engine into a 1999 body. It's been a long drawn out project and I didn't label the wires when unhooking them and now I'm stuck. I have a wiring diagram and I'm going to have to start tracing wires, but I already found a plug that I had to swap out because the different years used different plugs. Really don't even want to mess with it at this point, but going to have to do something with it.

Is there anything I need to look out for when doing the wiring? This is my first engine swap and I was definitely in over my head and it's finally starting to look like a car again and I've just been having a lot of trouble with the wiring and I'm wondering if I'm going about it wrong. Next engine swap, I'm going to very meticulously label the wires as I unhook them.

Picture of my car before I totaled it out