Number one will not detur a thief. I know of three boats locked and chained that had boats and motors stolen. One boat was on a larger boats deck, one was hauled up on davits and one was chained in the water. Two were stolen in Trinidad and one in Martinique.
Number two helps IMHO, had one cruiser tell me to paint the cowling white saying no one wants an Evenrude!
And three will be great if it ever floats free and you have to find it. But it seems in the islands most thieves don't give a crap about the dinghy. The one stolen in Martinique the motor was gone and the dinghy floating free. Anther cruiser picked it up and the owner claimed it the following am.
Ciao