Basenji Owner

We own two Basenjis, a female tricolor and a male black and white. The female is about 17 pounds and the male 28 lbs. They are Star and Comet respectively and both neutered. Star is about 6 years old and Comet about 4yrs both are purebreed. Comet was a rescued dog and came to us with some problems a lack of potty training, destructive behavior and some agression problems (mouthing and grooming nips which escalate at time to actual nips).  They get along well with each other with the female being the alpha of the pack.  I want to try click training with both of them (should I train with two different click sounds or just use the same clicker with both) They love to run loose but are not socialized well with other dogs or people for that matter, so I must be extremely careful to choose an area that is fenced and where I can see if anyone or another dog enters the area.  They will come some of the time, but not at all if another dog is in sight.  Extremely aggresive when on a leash and I want to work on getting them socialized with other animals as one of the other training goals.  My wife and I are getting getting very close to being Senior Citizens and the energy and strength of these two dogs some time makes it difficult to handle them both when on a leash because they want to attack any other dog regardless of size. They have in the past completely terrorized a pair of great danes that became nervous wrecks because of my dogs.  The owner moved away from our neighborhood partially because of them.  So I need help.  Click training sounds great and I look forward to talking to a trainer and getting started.