I've tested the export to github button for https://code.google.com/p/arbitrary-precision-float then completed the wiki export with https://github.com/morgant/finishGoogleCodeGitHubWikiMigration.
It mostly worked except a few links that I manually restored, and I can say that I'm satisfied with the result.
Note that the code is still not hosted on github, but rather on http://www.squeaksource.com/ArbitraryPrecisionFl.html or cincom public store...
There is also a fork in SciSmalltalk but for now I prefer to keep a standalone project because it has some value per se, and also to maintain code for more dialects. This will imply some extra sync burden, but it should be manageable.