That 'spark' point is going to cause you troubles. It is a bad connection waiting for a bad time to fail, like in a snowstorm or rainstorm or middle of a swamp or...
If you can see the arc under large load, the connection should be taken apart and cleaned and tightened well.
86/00 CJ7 Laredo, 33x9.5 BFG AT's, 'glass nose to tail in '00, 'New' frame,wires and plumbing in '09. Carter BBD Carbed 4.0 HO in '10.
89 YJ Renegade. BBD Carbed 4.0 HO. Locked front and rear with 33x9.5 BFG AT's
Some Canadian Bush Jeep Runs and Build Photos: http://mikeromainjeeptrips.shutterfly.com
(10 new albums added Sept 16/10)