The Clio III uses the Nissan B platform, co-developed with Nissan (which Renault has a share in), that is shared with the Renault Modus, the Nissan Micra, and the Nissan Note. It also brings the trademark "Renault Card" keyless immobiliser to the Clio for the first time. 

The factory wiring uses an ISO plug. No fascia is required to fit an aftermarket radio as the dash will only fit a single DIN radio.