Actually, I hadn't even thought about that- I was more concerned with trying to draw the bloody thing somewhat correctly, than in an amusing aspect.
Up until the middle panel, I'd drawn the car from memory, without references. It's simple enough and iconic enough that as long as you're close, people get the idea. But for the back view, I couldn't get the look of the hood right and so Googled up some pics.
One of the first results showed a car with a small oval taillight, and I was in the inking stage when I scrolled down a bit and there was a diagram showing the progression of Bug taillights over the years. The one I was drawing was from something like 1951.
So I altered the light to a more early-70s style.
I could have had the car sagging a bit to the side, but then again, I could also have given it the usual 40-year-old Alaskan-car rust, rock chips in the windshield, dents in the fenders, a trunk lid wired shut, etc.
The car sagging to excess to the side assumes a car from our world getting sat in by an 800-lb bear. However, we have to assume that Doc and Cara don't weigh as much as actual polar bears, if for no other reason than they're not 8 to 12 feet tall while standing upright. It also assumes that cars in their world aren't fairly regularly fitted to drivers of widely varying body shapes and accoutrements. I could easily see that their equivalent to a Midas, or the like, might fairly regularly swap springs or add or remove heavier duty shocks or booster springs, to adjust to the various critters.