The oldest thread I found for myself only goes back to 2008? That can’t be right.
Ah wait, apparently the search results are limited to 1000. Any/best way around that?
Answered my own question. If anyone else wants to do the same thing, use the Advanced Search option from the Search dropdown, search for posts or threads older than one year, then list in ascending order so oldest matches are returned first.
Search by Thread Start Date and Ascending Order, that’ll give you the rest.