I have changed a number of ballasts and it is super easy. You will need to remove the fans first as they are connected to the ballasts as well. Put some masking tape around the plastic fan fasteners so you dont scratch your fixture when you remove them. Also, be VERY careful when you remove the aluminum screws all around the fixture. Aluminum strips very very easy. Remove the middle fasteners first then the ones on the ends. You will need a pair of pliers to remove the plastic cord gromet.
Also, before you start be sure to remove all lamps and the acrylic cover. I know its obvious but just pointing it out. When you pull the main outer cover of the light off, just be very careful not to squish the reflectors either. Pull out the main section only as far as you need to replace the ballast. Block up the side you pull out to not squish the reflectors and the. Replace the ballast. All wires are colour coordinated so it is very easy.
