I have one of these boring and facing heads for over 40 years use.
You can not make the feed go in reverse it is a case of stop and manual wind back. (unless I have never found out ?)
Feed rate is on my head at least 0.004" per rev with one of the hex key buttons in the top knurled ring turned clockwise to engage and 0.008" per rev with two engaged. During facing operations simply engage one or two of the feed buttons and with spindle running simply hold the knurled ring. Let go when you want to stop. Chris