I got a HF 3 ton floor jack on sale for $68.88, 10x 96"x 2x4's cut in 1/2 from HD, and a box of 10d 3" common nails, which have more structural stability, less chance of splitting the wood, and a much better price then screws. I might need another piece of coroplast but will wait until checking the underside and seeing what is needed.
I've cut the 2x4's into 40x 10 and 14" pieces with a hand saw, which took a couple of days and was mild exercise. The floor jack lifts the car easily with the wheels more than 6" off the ground. The car was tilting to one side, but that will be high enough for the first level of boxes, and the total will be 6" higher.
The underside looks like this photo from daqcivic's thread on his
92 civic DX. This is a busy week for me, but I'm hoping to finish the boxes by this weekend, then will take a closer look underneath.
