Bridgeport Series 1 - Z axis oiling problem - need help

Greetings,


I'm in the process of retrofitting a series 1 boss 5 and i'm having
a problem finding out how the z axis ball screw is being oiled.
When i bought the machine the oiling tube had been pulled out.
i have dis-assembled the motor and pulleys to reveal the z- axis
ball nut and screw assembly. i can see a large spanner nut and
lock ring and a small tapped hole but no evidence of how the oiling
tube was secured or located. can anybody tell me where the oil tube
goes? how it is secured inside of the housing? and how the oil tube
is supposed to function? so that i can restore it back to its
original configuration.

Thanks
Jeff