I've added a SqueakMap link to the package model for package universes. Using this, you can now add a link to a SqueakMap package UUID if there is one for your package. SqueakMap supports more information about a package than package universes does, so maintaining a SqueakMap entry is a nice thing to do.
Here is what you need to do to add a SqueakMap UUID to a package universes package.
Update your universes installation to at least version 36. Open a universes editor and do "new package version" on the package you want to update. It is not good practice to overwrite a package entry that has already been published and in use, so add a "-2" or similar to the end of the version number. Change it to -3, etc., if you need to do any other updates before the next up-stream version of the package comes out.
Next enter a SqueakMap UUID for the package. Usually you can just click the "guess" button beside the SqueakMap field. This will look for a SqueakMap package with the same name as your package-universes package. If that does not work, you could try browsing to the SqueakMap web page for your package in any browser. The URL will include the UUID. If neither of these works, feel free to email me so we can try and figure out what the package's UUID is.
That's it -- post the new package and it should work. Open a universe browse--without updating!--and you can see and test your new package entry. The SqueakMap links appear in the package description field, right beside the hompage link and maintainer email address.
The tool support for this link, as you will see, is limited right now. At least, though, there is now a link within the model. This link is available to any future tools that want to reason about publicly shared Squeak packages.
Lex