On the giant jointed that I have, the lead is in the back part of the front section. Put in just below center at the join. Rockfish9 had some comments on these a while back. Might search for that. Some good stuff
Basically, you can place the lead in the back part of the front section, or do two shots: one around the chin and one around the back part of the front section. Each will give you a slightly different action. I chose two shots for mine, 3 1/2 oz, though a little shorter than the CCBC ones.
I also used Rockfish's method of doubling the front wire section to get a tighter join. I tried it this way and just doing a tail wrap on the front. The former gave me a better action.
Jigman