Google and some sites still link e.g. to http://llcon.sourceforge.io/sourcecodecompile.html, http://llcon.sourceforge.io/servermanual.html or similar. I think since maintaining two pages is too much work, I'd suggest to add a 301 Redirect (if possible) to the GitHub wiki sites or an info box states that more up to date information can be found on the GitHub wiki.