They're normally arranged as a series of 'T' shapes. For each bar of the 7-seg there's one jumper going from the centre of the 'T' to either the left, right or middle branch. Right/Left makes the segment light up when either High or Low, middle makes it always light up, remove the jumper makes it always stay off. Then you just need to work out which LEDs you need for which speed. I've guessed where the 'T's are in the photo, but I can't figure out which T goes to which segment. Does it currently show any numbers in either turbo or slow mode?