It's fairly straight forward - the only 'challenge' is overcoming the lack of a switched live on the Stilo ISO connector.
Depending on the make of head unit you are fitting you may need to modify the wiring which comes with it. I've fitted a Pioneer and Sony to mine and the Pioneer loom allowed a suitable wiring config using the bullet connectors on the live feeds however the Sony required the red and yellow cable positions on the Sony loom to be switched to acheive the same result.
The other solution to this cable switching is to buy an ISO extension lead and place bullet connectors 'in-line' in the power cables (red and yellow) to allow you to switch the positions quickly and easily.