[Mike V. Florida]

Let's see that the standards have to say;

"The rear lamp wiring was routed under the rear motor
mount to the bottom inside of the left rail and fastened
with a clip. It was then routed through the center cross
member with the transmission mounted stoplight switch
or under the cross member with the cross member
mounted switch, and along the bottom inside of the
lower left rail, fastened with three clips. The harness
was routed to the frame upper rear corner bracket where
it was fastened with a clip. Passenger vehicles with the
drum type rear lamp had two clips holding the wires to
the lamp support. Later models had the lamp extension
wires attached to the rear fender bracket or fender skirt
with a special clip. Beginning early 1929 a clip (A-
14592) was used to support the wiring to the bottom
of some wood framed bodies just rearward of the rear
cross member. The clip was attached to the left floor
sill with a #10 black enameled round head wood screw.
Applicable bodies included Fordors, Station Wagons,
Panel Deliveries, and 78-B pickups. All clips were black
enameled."

In 1930 the factory would not have wired an additional tail light so the method of fastening the the wire would have been up to the installer.

Sorry, but the uploading part of this site is down at this time to up load the different types of clips (page 2-16)