This hack by Lui
has some of the changes, such as the level changes, a Yoshi Coin indicator on the OW, and the autumn palette only after getting all 96 exits. It doesn't have the voice acting, changing to Luigi on the map with R, or the status screen though.
There's also a newer version
with 3 patches, a Mario version (both players have normal physics), a Luigi version (both players have Luigi physics, Luigi is player 1, and Mario is player 2), and a mixed version (only Luigi has his floaty physics).