How to add iframe clocks to website

[xekuter50]

i basically want to add one iframe countdown clock like this

http://www.timeanddate.com/clocks/freecountdown.html

to a specific forum. Not the index, just for one specific forum and i want to add an iframe clock to the sidebar of the index page.

Thanks in advance for any help.

ive gotten it to add to the index page header and footer btw. i just need to know which file to edit for those 2 specific needs.