Tipping on the Auto portion of the Auto Train

[bbappel]

I've read about tipping the attendants in the room and in the dining car. What I haven't noticed (and I could have missed it) is information on whether we tip the person who takes our car to load and the person who brings us our car at our destination. We are former cruise passengers, so tipping isn't a problem. We just would like a guideline as to if and how much.
I'm really looking forward to our first Auto Train to Florida. I loved train travel in the early 1960s when I was going between Ohio and Southern California for college. Then we were taking Amtrak from NY to DC for the occasional weekend when I was working in NYC.
Help is appreciated.

 

[OBS]

You will have little to no contact with the crew that loads and unloads the cars. So none is necessary.

 

[Dakota 400]

You will have little to no contact with the crew that loads and unloads the cars. So none is necessary.

The only person at Sanford that I had any contact with was the initial person that checked my car in and then quickly went to the next one in line. At Lorton, there was no contact with the person that drove my car off the car carrier and got in the line-up. No tips are needed.