Chris, I work on the basis that the crooks and smart arses of this world are always at least one step ahead of the real world. I'd get an isolator anyway... much cheaper than the excess on your D3! If you need someone who will do it neatly (mines under the bonnet and even I couldn't pick it at first..... very discreet! ), let me know.
There is another thread here somwhere where i posted the fact that some local hoods had a go at this party trick and I sprung them..... It's no urban myth, believe me