2002 ford powerstroke 7.3 turbo diesel f350

Hello I am looking into doing a swap is engine on 2005 Ford F550 from 6 litre to 7.3 litre. Can anyone tell me the process or is this is a good idea. It will done to a tow truck and current engine which is 6.0L has head gasket blown. Do I need to change the tranni and the wiring harness...