Fixing a T5 Light Hood

[KPG007]

Here's the story. I have a basic 48" - 4 Bulb T5 Light Fixture. I replaced it this weekend with a 6 Bulb fixture. As I have the 4 Bulb up for sale, I unplugged it, put it on the floor, flipped it over, pulled out the lights and cleaned the salt off the bulbs and reflectors. When I was done, and everything was dry, I put it back together. When I plugged the 2 banks in, the first lit up as usual, but the second one flickered for a few seconds, hummed a bit, then POP! lights on that bank are dead. I tested all 4 bulbs using the other bank and all work fine. Am I safe to assume the Ballast died? There was no electrical smell, so I don't think so.
What's worse is I pulled the hood apart, couldn't find anything obvious, put it back together, fired it up again, more flickering, humming and POP! now the OTHER bank is dead! What the heck is going on?!

Are the ballasts dead? I'm not an electrician, so I don't even want to consider pulling the ballasts and replacing them myself, espcially when I was only asking $200 for the whole fixture! Anybody got some options I can try?

Thanks;
Kelly