Need to add an ical button to an event

Hi, I have enabled the ical support for Events+ and adding the ?eab_format=ical to the url does download the ical file and allow a user to add the event to the local calendar. I would like to have a button on the event page itself that does this. Of course I would rather not modify the core files if possible, but will if needed. The idea would be that the user will display the event and be able to simply click a button and download the ical file. How can I accomplish this?