Starter change without battery disconect

I have a new starter to fit, but the car is imported with no manuals. I really don't want the radio to loose its code.

obviously not ideal, but cautiously can I change it without disconnecting the battery? what is the possibility of any damage to components.

I don't expect anyone to condone this way of doing things, but if you had to do it this way what precautions should one take.

Many Thanks

Matt