I didn't keep the grips and, if I need a new pair w/o heating elements, I would go with a thicker set. The stock grips are too thin for my taste. I just cut the old grips off with an exact-o knife and called it a day.
Make sure you have some sand paper available to clean the non-throttle side. I sanded the bars clean from top to bottom and also ran the sandpaper through the grips a bit to smooth the inside. I also sanded the throttle side just to make sure the supplied glue had a tacky surface to apply to.
Also, have a Dremel tool available. The end of the throttle tube has a lip on it. The new grips will not fit over the lip. I just sanded it down level with the rest of the tube.
To keep your fingers from being glued together, use a small amount of glue and watch the ends as you are placing the grips on. I am not a fan of glue and am used to placing grips on dirt bikes with hairspray, Before applying any glue, make sure you test your placement of the grips multiple times to have an idea of where you will be placing the grips. That helped a bunch. From my experience, peanut butter is the best at getting the glue off of it gets on your hands.
I did wire directly to the battery. I have heard about tapping into switched leads and such, but I was not sure which to go with or if it would effect how the troller works. The electric troller apparently has a voltage check built into it. With the unit connected directly to the battery, if you leave the grips on accidentally, it will monitor the battery voltage to a certain low point and then, automatically, shut the unit down. I was concerned that wiring it to something that had current and voltage changes would cause the troller to shut down. Of course, I don't claim to be an electrician, so I thought a clean job the first time would be a good job. Like a carpenter would say, "Measure twice, cut once."
I think that is all I can suggest. Take your time and you will be more than satisfied.