Add Combo Boxes to Replace My Lists

[OkayKid]

I have been researching this extensively and have found lots of forums and articles relating to it, but they haven't worked for me. One of the reasons I want the combo box is to make the drop down arrows visible at all times.

Here's a sample of my drop down lists:

http://postimage.org/image/2ym2o5dz8/

I'm using excel 2007.