So far as I can make out post#21 schematic is an early version, post#64 schematic is a later version, top right of both full schematics give the serial number change.
Earlier serial number version:
http://sportsbil.com/tandberg/huldra-8-sm.pdf
Later serial number version:
http://sportsbil.com/tandberg/Huldra%208%20skjema.pdf
Lawrence.