Here's a not so good photo of the real car, but I had it handy.
I took a bunch of pictures when I had it on the rack so getting the colors for the underside was easy. While the kit is a ’97 and mine is a ’98 there should not be much difference. But for whatever reason there are some discrepancies between the molded part and the real car. So I painted it to match the real car as much as I could and didn’t worry about the differences in the molding.
Instead of masking and spraying I freehand brush painted everything except the gray panels. It was easier than masking. I added a little dirt and grime as I went along too.