A Research Question: Is John Marburger the Longest Serving Presidential Science Adviser?

Dear readers: I'm working on something and could use some research help from any intrepid minds. It seems to me almost indisputable that John Marburger, who assumed his post in 2001 and has continued it now into late 2007, is the longest serving presidential science adviser in history. A quick glance at the terms of previous science advisers--see here--strongly suggests that this is so. However, you know how it goes with government: There are technical details about when the adviser was actually confirmed, when he actually departed, and so forth. So: Does anyone disagree with me that Marburger is the longest serving adviser in history? And, does anyone know how we could get the actual precise dates for the terms of each adviser so as to prove it for sure? P.S.--Last week I did a DeSmogBlog item about Marburger declaring that the earth would become "unlivable" if global warming goes unchecked. It was entitled "John Marburger, Climate Alarmist?" You can read it here.