How can I make Spotlight index source code in Mountain Lion? Under Lion I had Spotlight set up to index .as (ActionScript) files using the general instructions here: http://hints.macworld.com/article.php?story=2005052015041510
but installing Mountain Lion seems to have broken it.

I went to /Library/Spotlight/ to try again and found that RichText.mdimporter no longer lives there. And the alternate location, ~/Library/Spotlight/, no longer seems to exist at all.

When I follow Apple's instructions here: https://developer.apple.com/library/mac/#documentation/Carbon/Conceptual/MDImporters/Concepts/Troubleshooting.html to check which Spotlight plugins are installed by typing "/usr/bin/mdimport -L" in terminal, I just get a blank list with NO plugins.

I don't need anything fancy, I just want Spotlight to treat .as files as text. Any ideas?
As mentioned in your linked article, the default place for all included importers has been System > Library > Spotlight since 10.4 and it's still there in ML, including RichText.mdimporter.