Install CR97 (1nF) and R106 from the bottom side otherwise the Mode Switch will not fit.
BU -battery Wire port 28 (not sure what to expect here but I measured somewhere around 6VDC iirc)
6VDC Wire port 30
15VDC Wire port 33
5VDC Wire port 34
Issue 1: (see service notes from Roland to check the correct layout)