why a low battery code? because he disconnected?Should be good to go. They will see a low battery code. But a spray pattern on the piston is noticible if they want to get technical.
what's it going in for? if the HG are gone and the pistons show signs of overfueling they may be required to get authorization from a ford inspector then your screwed.buddy has an sct livewire and hes getting ready to take it to the dealer,he put back to stock and unhooked his batt' s and turned his headlights on for 10 mins should that clear everything or could they still find it.