2000 Dodge Dakota Headlights Question?

[C. Shelton EMT-B]

I am hooking up some wig-wags(headlight flashers) to my 2000 Dodge Dakota and the Whelen instruction manual says there's a ground-side switched, or positive-side switched style system for headlights. I have no idea what either mean, or which one my truck is. I've googled it and came up with nothing, and went on Whelens website and could'nt find it either. If anyone can help, it would be greatly appreciated. And just to let yall know, I'm an EMT and am not going to be impersonating an officer. Thanks guys!

 

[Zimmer]

With the lights switched OFF connect your meter or test lamp to the lamp terminals.If you get a reading the switch is on the return side.if you don't get a reading the switch in on the feed wire