the marelli the food from the comb, the adapter must be placed between the cock and the e xxx, spring and "not" go, powered on, e xxx has, of course, the verse that is to be respected otherwise you can ruin the ecu, also if many say that powering it from the comb do not ruin, do not trust it, I don't know the verse so about two feet but there are documents that explain it, I forgot the adapter has its own verse, if you look in the documents of the rooster there are a lot of photos with explanations.