I used krylon fusion, and no primer is needed. It says no sanding is needed either, but i still did it. Snaded it down, cleaned them with degreaser, then soap, dried them completely, then you spray VERY like coats on at first, this paint is very sensitive to heavy coats, and WILL run and chip easy if not put on right. Then i put Krylon clear on top of that, which made it glossy. Some memebers on here have had problems with it, mine came otu perfect, so problems here. If your fenders will be flexing alot, as in you have front fenders not race cut, then i dotn know. Both my front and back are chopped. If you need any more help, feel free to ask me.
Heres what it turned out to be like:
Yeha, i know it looks funky the way it sits, no tie rods on it
Eric