I am trying to set up some fogs. The toggle I am using is one of those three pronged ones with light up red when its on. I have all the cables ran, and the ground of the toggle is good, but I keep on blowing fuses. Could it be the ground for the lights itself or something else. First I had the power to the fuse box and that blew two fuses, then I had the power directly to the battery then that blew the inline fuse. Any ideas?

You're shorting somewhere, Check all your wires for cuts and knicks. esp where you went through the firewall.

The power wire coming from both the fogs were not long enough to reach the cab, so I had to add some more length to it. I simply twisted them together then put a twisty cap on it to cover the exposed wire. Maybe the instructions are wrong, they had me put the ground wire for the toggle in the middle prong. Can I hook up the ground for the lights themselves to the negative terminal on the battery?

It'* not that you can't... but it would be better if you use the frame itself (kinda like when you jump start). Just about any bolt/screw will do, as long as it is metal and it'* attached to metal.

And as far as the twisty cap connection, could the open end be touching any metal (creating the short)? If at all possible, you should completely seal every electrical connection with electrical tape to prevent any heat buildup or arcing. Treat it like a radiator hose connection... it should be tight enough everywhere to prevent any possible "leaks".