TV3 Ignition switch

[Littlewheels]

Can I use a 4 pole 9 wire TV3 ignition switch on a 6 pole system?

[hullygully]

can't see why not bud

[Fast n Furious]

If you are using the AC 6 pole stator (one yellow wire type) then the yellow wire replaces the brown wire from the 4 pole plate.
If using the DC 6 pole stator (2 yellow wires) then just ground the 2nd yellow wire if you are intending to use an original TV2 early TV3 selenium rectifier.

Most of these 60+ year old Selenium diode based rectifiers, unlike later Silicon diode based ones, are no good really because Selenium diodes degrade with age. Consequently, because of the increase in forward bias resistance in these old diodes it results in neglible ability to charge the battery properly. Best to replace this old rectifier with a modern Silicon rectifier.
To make this easy I use a 35 amp rated block rectifier KBPC3510 simply because they are cheap and readily available even though they are technically an overkill but wire it up as a series /parrallel half wave rectifier arrangment rather than a full wave rectifier.
These block rectifiers are easy to mount in the original case once the old selenium unit has been removed. Best to solder the 2 wires onto the 1/4" tab terminals rather than use recepticle connectors.
Because these old rectifier casings have seen better days, they have high levels of oxide and crap on the bullet terminals. Some concrete cleaner and a small artist brush will make quick work of bringing these back to bright again. (Just remember to wash it off thoroughly with water when your'e done)
The yellow wire from the stator needs to connect to the -ve terminal of the rectifier. The internal inductor / purple wire termination needs to connect to the +ve rectifier terminal.
The 2 AC rectifier terminals can be carefully removed with some sharpe cutters or insulate off with a bit of heatshrink.
Works well and retains original look.