I don't think there's any splicing involved. In most cases, plug and play lang yan. I'm not sure what the head unit of a 2007 Prado looks like but I'd say that replacing the head unit is 99% worry-free so finding a good shop isn't hard as it looks. Just check your friendly suki talyer.. if not, tell me your general location and I could suggest shops that can do it for you (sadly, the shops I'm suggesting are those big-time shops.. just drop by Banawe anyday and everybody there can do it ;D)