Yup, which is pretty much the standard arrangement using that sort of switch, with dyn and regulator.
The 4 terminals used are:
#2 - for powering the dipswitch and through it therefore the headlight (and horn)
#3 - power in, from battery via ammeter (also connected to A lead from regulator, either directly as in Julian's schematic, or via the ammeter (as here if it pops up) but same thing). If the battery falls off (!) or is otherwise disconnected then regulated dynamo juice comes up the A wire - and things keep working (flickery at low revs, ammeter shows nothing)
#4 - front pilot light only. Goes off with headlight on
#5 - tail and speedo / other instruments. Stays on with headlight
If unsure of switch behaviour, a meter on the resistance scale will show which terminals come live/ go dead / do sweet nothing in each position. Terminal #3 being the source of all goodness.
Good luck!