It's ok to unscrew the condenser and take off the baseboard but don't go beyond that UNLESS you are prepared to spend frustrating days trying to align it back up! I took it apart to rebuild it and it took me days to get it right again and I had to borrow an alignment tool to do it.

Yes, it is a D-2 with VC. When you twist the lower condenser off, make sure it's how brucemuir describes it. D-2 and D-II came with 4 different condenser at one time. VC supposed to have the largest one where lens occupy the full diameter of the aluminum outer casing. If anything else, it's a wrong one. Plus, make sure the drawer has the movable lens in it.

Before you try to move it, make sure it's locked up. If you look lower right of the beam, you will see a small plastic locking "thing" with a thumb screw on it. Otherwise, the carriage will slide up or down while trying to move the whole thing.

I have a D-II with VC and D-2 with regular condenser. They are great, stable enlarger.