Probably not much. It happens in the Army to. Not supposed to, but we had "hanger queens" in some units, piece of equipment is down for a part, and that part isn't coming in from the States for a month, guess we can "borrow" some parts off of it to keep the rest of the equipment up. Just takes one surprise IG inspection to ruin a career or two if you make a habit of that though.
Hmm didn't think borrowing parts off the other aircraft's was not a good practice. Most of the time we transferred the equipment serial number over to the aircraft receiving the part, so it was known in the ACFT forms. You gotta make your sorties...and a downed aircraft waiting on a long lead part, while another aircraft is down for a long depot or TCTO, makes sense to grab one off it.