The 4 optimas are nearly 250 additional lbs, and would likely fit right in the spare tire well, so all the weight would be supported by the rear springs. I like the air spring concept, but it is not clear yet if we could fit one in the spring space. Heavier springs are another option, but we would have to have the rear fitted with all the batteries to be able to spec the required additional weight capacity.I picked up two of the air springs, and will try my luck at installing them over the weekend.
As the photo shows, the air springs are a bit on the big side.
The springs are loaded with 150lbs in the right hand photo that shows the air spring.