headlite question

I have gotten the headlights all working. I remember 4 yrs ago when I picked up this Toad cleaning all the grounds but I have also added one from Neg Batt. terminal to rad. support like all the 63 up cars have. Also replaced 2 of the bulb sockets, and a ground wire to sockest on one side of headlite bucket. I have a little volttage drop from firewall to connectors at headlights. No doubt the wiring is 50 od years old, I did clean all terminals too.
I noticed after I had gotten th dash somewhat apart someone had spliced into the black main wire at headlight switch. I can npt get to it right now to see exactly what or why.
This Toad was a pace car at a dirt track in Mo. years ago. It had a 2 way radio, fender flags, and a toggle swicth to turn the back up lites on and off!
Thanks for all the input. Life is good ( as soon as the humidity and temps drop a little!)