If you go to your own profile page, click on the "topics" you've started under "activity", a quick scroll will take you to the build thread you want...even after years.
Another easy way is a google search with your screen name here and the title of the thread. That works pretty well too, if you can remember the thread title. But don't bother trying that with duckduck and some of the other second string search engines, as they're not really very good.
Google tends to downrank threads that haven't been looked at for some time, so you'll get a lot of non-relevant results, especially as google gets dumber and dumber these days....AND it's often easier to find your old threads on google if you do an image search using the same terms (that works well for me anyway, as I instantly recognize my own photos).