I was gonna jump on you and say search newb, but come to think of it Im not 100% sure we've had any luck swapping a neon 3-speed. Im pretty sure it's been done though...

Edit:

http://forums.2gnt.com/dcboard.php?az=show_topic&forum=33&topic_id=2345&mode=full

Looks like a lot of work, though you would be able to use MegaSquirt with this change very easily. Pro's and Con's to it, check it out.