I submitted the old board's addresses to archive.org through the alexa crawl.
Sites are usually crawled within 24 hours and no more than 48. Right now there is a 6-12 month lag between the date a site is crawled and the date it appears in the Wayback Machine.
What's there so far (up until March of 2005) doesn't include the message board.
http://web.archive.org/web/*/http://www.sonicyouth.com
From April '05-March'06 is missing.
I couldn't get anything to come up with the folders of /gossip or /bboard/fanforum, but I submitted these. Since the new board also uses sonicyouth.com/gossip, it has perhaps kept the old ones from being able to be archived, but hopefully, the bboard/fanforum address that was also submitted will make it into the wayback machine at some point.
I just tried it again, & some of the pages from early 2005 do work & are partially there.
try going to the gossip section from this link:
http://web.archive.org/web/200503300...onicyouth.com/