While a backup camera would help, I find that I can get to the correct spot in two tries most of the time. I.e. initial approach, get out and check distance, reverse while watching for same distance passed by looking at ground as it passes the open driver's door, get out and check again. Maybe one more truck movement to adjust.

This usually works out much better then having someone else try to direct me.

That said, I would still like to have a good backup camera.

I am actually thinking of making a battery-powered (and wireless) one that I can stick on the back of the truck when hooking up the trailer, and move to the back of the BOAT when on the road.

It's amazing how many people feel obligated to tailgate behind a boat/trailer... much moreso than behind a regular vehicle. I know a couple of people with destroyed stern drives because the driver behind simply did not comprehend the 3-foot-long object sticking out the back. Eesh.