Yeah, speaker wires will fit through those holes, I'm working on mounting a pair of 6" OZ brand speakers in the doors, or rather in and on the doors, since they won't fit flush.
The remote door locks system is so nice, I also have the power trunk release installed.
I bought an Audiovox system off Amazon for about $25, 2 remotes and everything I needed except had to add my own relays to power the actuators. Instructions said I didn't need to, but I had a bunch of 30 amps ones laying around so used them. Only thing missing is an inner switch to lock/unlock manually, but I don't miss that...