You can upload multiple OFs on to a PS3 by uploading them under different User Names on your machine. I'm not sure how PSN accounts factor in here, if they do at all. The key is to use/create multiple User Names.
Check out ¢Ħλ®₤ỉξ-[14]'s thread. He did a lot of the new 2011 MLS kits, including the Fire:
http://www.pesgaming.com/showthread.php?t=81008
The first post of the thread has all his work collated, but you might want to poke around internally in the thread for his specific color-code recommendations. For the Fire home, I think it's 23-1-1.
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Side note on the file: I'm going to stop calling this a beta, but we're continually going to try to improve the file, especially when it comes to kits. The guys who help with PNGs (venado & ¢Ħλ®₤ỉξ-[14] for the 2011 ones, in particular) do a great job, but sometimes the constraints of the in-game editing options make it difficult to accurately reproduce the kits. Partly because of this, we didn't include the 3rd Philly kit in this update, even though a couple of people requested it. The ugly 2nd one is still there. If we can figure out a way to accurately re-create the Philly 3rd, or improve on any kit, we'll try to do so in a future version/s.
Sorry if that disappoints any Union peeps here.