Geezus? What the hell were ya applyin' for, Chris?
It's been 15 years now, but chris_'s suggestion of 60 pages sounds about right to me.
I recall about that many pages when I was the records supervisor for a private contractor to Immigration & Naturalization. I don't know what "class" the clearance was, but out of 500 employees there, only two federal employees and I had that level. It was necessary for me, so that I could get into records of other federal agencies (FBI, IRS, whatnot).
It was a lot of pages, that application, and I had to go back a lot more than just seven years. Sixty sounds about right, and I had to append several pages of my own.
The Office of Personnel Management sent a little pit-bull of a guy from Kansas City to interview me; it was an interview under oath, and lasted from 4 p.m. until 2 a.m. (I worked second shift). He personally interviewed most who had known me since I had first been in Lincoln more than 20 years before, which was a lot of people.
He was working out of an unoccupied office at Immigration & Naturalization, and had stacks of personnel files on the desk and table. Most of them were 2-3" thick. I got nervous when I saw mine was the biggest, easily more than 6" thick.
It wasn't that I had done anything wrong; it was only because I had done so many different things.
He even had copies of records of my visits to the U.S. embassy in Kiev (which wanted nothing more than for me to use my return airplane ticket.....from my sixth day in the socialist paradises). I was not aware the embassy kept such records, and was illuminated greatly about what had happened (i.e., things that had been a mystery to me were revealed; it's always been my fate to learn what's going on long after it's happened).
Due to the nature of his job, the pit-bull had to be antagonistic and confrontational--he was probably otherwise a nice guy, one of the nicest guys one could ever hope to meet--but obviously I did okay, because I got that level of clearance, with no conditions, that only two other people there had.