Help with RNS-D conversion

hi, i have a 2001 s3 with single din bose stereo, i have just bought an RNS-D sat nav from a 2002 8l s3 with code, is the conversion pretty straight forward or would i be better getting someone to do it for me, what else will i need to fit the RNS-D to my car, i am aware i will have to move my climate control unit and trim the sides down to fit lower down in the dash, i will also need a double din cage, what else will i need, should i already have the wiring loom in my car or will i need an extra loom, any help would be appreciated thanks

all i have got is the unit and the code no wiring