I ran a 5 wire flat female plug from the front of my F150, headed up towards the battery, grounded the white wire, took the blue to a fuse and then to the positive on the battery.
Continued on with the yellow, green and brown through the firewall at the back of the fuse box and into the passenger footwell.
Remove the access panel at the passenger footwell and you will find a junction box with a large lever type connector and several normal multi pin connectors.
Remove the large lever connector and tap the following:
Green to purple/pink. (Right turn/stop)
Yellow to tan/brown (Left turn/stop)
Then remove the tan plug on lower right of the big lever plug and tap the brown wire onto the yellow/green wire ( tail lights)
Finished should look something like this:
I then made up a short connector to go from the 5pin flat at the front of the f150 to the round connector on my motorhome. I embedded diodes into this connector to isolate the f150 from the MH and added another fuse to the charge circuit so its protected at both connections. Works great!
Front view of F150 with hidden draw bar connectors, 5 pin electric and brake away connectors.
Hope this helps!