Todd,
I think the problem might be the color coding on the wires on the Lucas headlights. Check which color wire you have as ground. On the Lucas lights, ground is green.
The "I" on the regulator is the excitor if my memory serves me correctly. As long as you have done the wiring as shown in the Painless instructions, you're OK.
As far as the horn goes, I'm a bit stumped there. The horn wire on the Painless kit is the green # 924 and should go to the horn. As you said, the other side of the horn circuit goes to ground. The horn wire comes from a relay, but I would think if the fuse were removed the horn would'nt work. Are you sure you pulled the right fuse? Check again, just to be sure.
Jim
