To followup on this thread, the horizontal white bar should be laying flat. In the first picture above, the white bar is upright even though the metal rod has not been engaged. The comment above by Martin, is that a small spring on the right side should be pulling on the bottom of that white bar which will keep it flat.
Here are some detail instructions for the non-experienced serviceman: You must put the turntable into service mode. To do this, 1st-remove the platter paying attention to how the belt is attached. You will need to reattach the belt when finished; 2nd- push tone arm assembly towards center of turntable (push from the back on the large square part, not from the tone arm itself); 3rd-lift up right side of turntable so you can access the bottom. There are two small Phillips head screws along the right edge. Remove those screws while supporting the bottom of the turntable; 4th-lower turntable back onto your workbench and lift right side of the turntable top. It is hinged on the left side. There is nothing to hold this open so you may need someone to help hold it open for you. You are now in the service mode.
The right side should now be fully accessible. Check to see if a small spring is attached on the bottom of that white bar. You will likely need tweezers to reattach the spring. In worst case scenario, That spring came loose and is lost. That spring is listed with reference number 1638 in the service manual. With luck the original spring is still attached on one end.
