FAQ: T44 trailor hitch

[Kneale Brownson]

Probably a good idea to add a fuseholder and fuse to the line at the battery.
   
  If you get one of those relalyed trailer wiring converters with a trailer pigtail, you can relay all the trailer light functions at once for about the cost of purchasing individual relays for four circuits.. 

Ben Swann <benswann at comcast.net> wrote:
  Anyway, I ran a 12 guage multi strand wire($.09/ft at Home Depot) from the
Battery + from under the seat to the left rear where I'm tapping into the
wires in left taillight harness. Ran this inside of a plastic wire protection
sleeve as an added measure so it won't chafe and short. 

Relayed the 12 Guage positive to terminal 30 on Bosch light relay through to
the tailight converter wire for the running tail lights. 

I used one of the .5 mil wire as the relay control (relay terminal 85), other
side (86) to ground. 

This worked great, nice bright light to the trailer lights, no risk of burning
out car wiring. 

I'm tempted to relay the turn signal and stop lights as well for nice bright
lights overall to the trailer.