Couple of things not mentioned so far that might help:-

35710 on the switch in your image is absolutely correct for your bike ("43 69" - Week 43,1969 manufacturing date - suggests it's original?); 35710 works exactly the same as 31788 and they were fitted interchangeably '68-'70 (to '74 on the T100).

Originally Posted by splash
tried to read the schematic in the manual without luck I see 8 numbers manual and only 5 terminals
Look more closely at the switch, "1" to "8" are moulded on the casing by each terminal or rivet hole ...

Originally Posted by splash
no idea what is up or down.
The switch should only fit in the headlamp shell one way - the shell hole should be D-shaped, the switch thread has a flat on one side. Mounted in the shell, wire colours connected to the correct switch terminals: switch lever to the left is all lamps "Off"; lever to the right is tail-lamp, clocks lamps and headlamp on (centre position is tail, clocks and pilot lamps on). Pilot lamp connected to terminal #6, headlamp (handlebar hi-lo switch) connected to terminal #8, both 35710 and 31788 turn the pilot off when the headlamp's on and vice versa.

Testing the switch out of the headlamp shell, amplifying post 834679, use either an Ohm-meter or a multi-meter set to Ohms, one meter lead end connected to terminal #4 (input from ignition switch), the other meter lead end connected to terminal #6 (pilot lamp), #7 (tail and clocks lamps) or #8 (headlamp) as required for testing; meter displaying very high Ohms is switch 'off', zero Ohms (on an analogue meter, near-zero on a digital) is 'working'.

Originally Posted by gavin eisler
Does your bike have an ammeter, if so, the double brown white would connect to one side of the ammeter.
Uh-uh, Ammeters have two studs with nuts, corresponding wiring terminals are rings.

Tape up the Zener spade terminal, don't cut it off the two Brown/White wires, that'll disconnect 'em and you'll lose the connection between battery -ve and the ignition switch.