Remember, no matter what, 42% Front, 50% Left, 50% Cross weight is where you want to start. Here is what I would suggest for a process. Being a little bit scientific about it will help in the end even if it takes a lot of time up front.
Strip all the lead off the kart. Scale it with out any additional weight. Set your camber at -0.5 on both the right and left front. Make sure your stagger is even left to right. Get the kart to scale to the numbers mentioned previously. From that point, start adding lead 2 5lb pucks at a time. One to the front, and one to the back of the seat. Repeat until you hit your total weight. Keep splitting the weight high and low on the seat as well. If you see the nose weight is already where it needs to be, then keep stacking the weight on the seat if you can. You can stop placing it up front.
Nose weight will change, but if you stay between 41% and 43% you will be okay. I seem to find that unless you are on really hard tires like vega reds or something similar, the limit on the nose weight is 44.5%. The YLC's seem to give up pretty quickly with that much nose weight.
If you can get everything to scale out with those percentages you should have a good base to tune from. Keep in mind you may need to adjust the camber a little bit to really get the weight percentages dialed in. But try not to go crazy. As long as you are with in 5 lbs difference in weight between the LF and the RF while keeping the percentages as close to 42F 50L 50X as possible the kart should drive a lot better.