The oil that is in the system as standard should pick up under UV light. Certainly when I had a leak, it was fairly obvious where it was coming from in a dark garage under a UV torch. Didn't need any specialist die to be added.
The only difficulty might be that some of the pipes go behind the firewall and then I assume you'd need some sort of camera that can feed behind the dash. Definitely start with under the bonnet though- that's where pipes, condenser, seals etc have to deal with the elements and stones being kicked up driving.