Hi,
Some comments on your posted pictures:
Pic 1: This is the tumbler reverse for changing the rotation direction of the leadscrew or feedscrew.
Pic 6: This lever closes the half nuts for threading. You can't do cross feed and threading at the same time. Only one shaft can be driven at a time.
Pic 5: not sure.
Pic 8: Banjo for change gears.
Pic 4: Cross feed selector.
Pic 2: Gearbox gear selector lever. (see chart for different thread selections)
There is a manual available for download here which might help you a bit:
https://cncmanual.com/viceroy-lathe/
Yours looks like an earlier version.
Regards,
Les.T.