Big Red T

guys i want to know how easy this can be done? i have an 06 sti hawk with 3"turbo back milltek walbro pump 7h plugs green panel filter and mapped by jgm. Amate has bought an 06 sti hawk and wants me bits as i may be changing the car. Can these ,more importantly the ecu and keys just be swapped over to his,obviously the rest can be swapped easily,without putting bchecklights on etc.he can always get jgm to check the map but that would be two months away.Iwould presume mine would be fine as it would just be back to standard. Is there anything else to cause hassle ie the alarm or the tracker or anything connected to the ecu? Its either cheap modding for him or a shame for me to let the bits go with the car as it would be going to a dealer who will give me nothing extra for them.