If your springs are the issue, then swapping sides should do something, even if it doesn't fix it. The right side axle perches are taller on all 80's, and your right side measurements are higher. If your right side springs are taller, then swapping them to the left side could fix the issue, or possibly make the left side taller than the right. Either way it tells you something.
If your springs are actually the same height, as the manufacturer says they should be, then the springs aren't the issue. The right side axle spring perches are only about a half inch or so taller than the left. Your measurements show a 7/8" difference in the front and 1.5" difference in the rear. If, for some reason, your right rear spring was (way) too tall or too stiff, it would also lift up the right front. The same effect could be from the left front spring being way too short or weak, or an extreme amount of weight on that corner. It's pretty hard to put extra weight on that corner. Maybe one or more of your springs are from a different kit, and are either too tall/short or are a different spring rate. Or maybe your frame is severely twisted.
Please post some pics of the bottom of the springs showing the coil end, like in
post #25, and of the top, so we can see if the springs are installed correctly and if they have any spacers. I don't see how you'd get the 1.5" difference in the rear just from having them installed incorrectly, but a tall spacer on the right side might do it. If they are installed correctly, you will need to remove the springs and measure/compare the free height and wire thickness. There aren't many other options, aside from throwing parts at it, which is not something I'd recommend.
