Funny thing happened, though, when I went to pick the batteries up. I thought the left rear tire looked a little low when I got out at Northeast Battery's parking lot but didn't think too much about it. Well, when they lowered the pallet of batteries onto the truck-bed I couldn't believe how much the back end dropped! I looked at the left rear tire again and it was obvious now (with the weight added to the back end) that the tire was basically flat. It didn't look like the front tires were in danger of losing traction because of the imbalance, but it didn't look that healthy, either. Yikes! So I limped to the nearest gas station (less than 1/4 mile away, fortunately) and filled up the rear tires. Man, I was sitting there for a long time filling that left tire - I topped off the other one, too, while I was at it. The truck was much more level now, and I felt much more comfortable driving it with the load. So no worries getting back to my home town (just under a 50 mile drive). The truck actually rode a lot nicer with the load in back, though I was careful to leave plenty of space in front of me for braking, and was ginger going around curves.
Here's the happy picture of the batteries in the back of the truck.
Loaded. (Don't ask me why I placed the yardstick upside down like that) We're at 19 inches here.