tranfer

My 2 yr PCP is coming to an end in 4 weeks and I need to take my number plate off before it goes back..... Is it more expensive to put a plate on retention (£80) and then transfer it to my wife's car (what does it cost to do this)? or is it cheaper to transfer it immediately? If I do it...

Is it possible to tranfer a newly reconditioned 230E 1981 engine, which has a working air conditioning system attached, to a 230E 1981 that doesn't have air conditioning system... What kind of difficulties are invovled with the tranfer of the airconditioning system....