Alignment - this is a one-off process when putting a ribber with a new machine (although occasionally if I’ve been using thick yarn, the horizontal alignment can require re-tightening). I’ve had various Brothers and the ribber required re-alignment for each one! :)
Pull some needles at the ends of the main bed fully forward, and have the ribber in the highest position
MINIMUM - you should be able to slide a piece of paper in the gap ‘twixt extended needles and ribber gate pegs
MAXIMUM - ditto, but the thickness of a CD
Adjust the vertical alignment at both ends by loosening the hex nut (sits between the back of the ribber bed and the rise-and-fall bracket) and then raising or lowering the little metal lever there. There should be a spanner with your ribber things. Re-tighten when done.
DON’T adjust this unless you have a decent sponge bar in, ie the main bed needles are flat against their bed, because if it’s a flat one it’s entirely possible to set the ribber too high and it won’t pass at all, ask me how I know!
There are two slotted screws in the bed of the ribber at the left hand end. Loosen them by one turn only. Set the ribber to P5 and tap at the end of the beds until the needles either side of 0 correspond exactly to those on the ribber. Don’t forget to re-tighten!