Bob,
The lift is required because of the size of the tank. The 3000 series tanks are a bigger, so the center of them is higher then the 2800 series which can use a magnet on the base to spin them instead of the lift. The lift actually has two locations to attach the different type of tanks.
If you are planning on using the 3000 series tanks, check the serial number to determine the age of the machine. Recent processors have a stronger motor which is better for the larger tanks. The info can be found on the Jobo website under motor upgrades.
If it is an older model you will want to upgrade the motor. Its not hard to do and the parts are available from Jobo.
George Losse