how did you get the rocker panel off? those bottom push plastic pins are in there good. I have one half way out and I cant get it to come out.. =-/..
also your taking in your car parts painted without it being on the car? I was going to do this but others thought it would be better to have it on the car that way they can paint match.. but of course its its on the car they will not be able to paint some covered spots.. but you want them to paint match too =-/ ahhhhhh
Those pins if I recall are almost two inches long and are stubborn to get out without breaking them. Sometimes it takes pliers.
As far as paint match goes with mine being Ford UA black it's really not a big deal. My painter already did my 3D Carbon fender vents and they match my fender perfectly. Your car is yellow so blending might be necessary.
I understand your frustration on prefitting the parts. On the other hand if you gave your body/paint guys the parts and they didn't fit right they are going to charge you for that time. I try to save wherever I can. So me I would pull the OEM panels, prefit the new ones and have the bodyshop, disassemble, paint, reassemble and blend. Nothing is easy with paints of color.