ford f700 brake system diode in wiring part number

I am looking for information about a diode used on ford f 700 series trucks. it is located in the brake light wiring near the driverside kick panel. it is used to stop the flow of current from the turn signals and flasher unit, prbably to stop the dash indicators or front turn signals from coming on when the barakes are on. I cant find a part number or value for this part, i have made my own by using two 3 amp diodes together. does any one know the value the diode needs to be. or a ford part number. thanks email me at hopsing2009@yahoo.com be sure to put ford diode in the subject line so i will see it past all the junk mail i get