If you must, just let Seas0npass do it. A word to the wise, though, here’s what happened to me, and it might not happen to you…
I had a functioning 5.0.2 running ATVFlash(black) with Plex and Infuse. I let the plex server update. I then began having issues with failed streams, cant open, error etc. I was not thinking straight so I did the 5.3 update, thinking that would fix it. I forgot that theres no Plex for 5.3. So I installed XBMC, didnt like it, and decided to downgrade to 5.0.2 again.
I have been having nothing but trouble ever since. Attempting to install either Plex or XBMC crashes the ATV. I get constant “no signal” then apple icon then “no signal” ad nauseam. I have updated to the latest, downgraded to older (down as far as 4.4.4) and eventually realised that half the problem was the plex server software so I downgraded that.
STILL geting crashes. I suspect that allowing a full update by Apple has caused some issues, thoguh I cant see why it would. I have now completely given up and have 5.3 with Infuse. I’ll continue to airplay plex from my ipad, but its infinitely annoying that the client on ATV is so crappy. Then again, its OLD.
I hope you have better luck than I did, with XBMC (because I was also going to install PleXBMC… but I cant)
Its turned into such a nightmare I am now on the brink of buying anotehr mac mini to use as an HTPC instead.