If, by lead uppercut, you mean just throwing an uppercut at an opponent, then it probably is not advisable. It is a punch that opens you up, especially if your distance is not right, etc...
As the first punch off a slip, etc...as a counter, it can be very effective. I can't think, off hand, of southpaw fighters using this much, but I can think of two fights where orthodox fighters used left (which is what I guess you meant by 'lead'-lead hand?) uppercuts against southpaws.
The first is Bryant "honeyboy' paden vs tracy spann- I don't have time to find it at the moment. But Paden enjoys success with a sneaky lead left uppercut, until the 4th round when Spann nearly kills him with a right hook. One thing that happens when you lead with that punch.
The second is probably more what you were looking for, and, as usual, focuses on Ricardo Lopez

Lopez finishes the fight with a beautiful left uppercut in the 8th round. He is tall for his weight; if I recall, you are as well? Watch what he does, then do it backwards.