thought id put that as a title so i can just add more and more questions

bought a efi head, inlet, loom and all sensors today for a bargain of £40

ive labeled up the loom and im left with a plug with 7 wires that went into the loom of the fiesta

my first question is how many earths does an xr2i engine loom have because i have one that i know is an earth and 2 brown wires that were stripped and twisted together, these were located on the passenger inner wing and look like earths but cant be sure

first of many questions