Leafs and torsion bars. How do you tell?

Leafs and torsion bars. How do you tell?

I now have new super stock springs and torsion bars. I read somewhere that someone had installed the left side on the right and vice a versa. He wrote that they were marked wrong. I would like to install them once. How do you tell?

Also I read that torsion bars have a front and back. They are marked left and right but not front and back. How do you tell?

Any help would be good.

Thanks

Luis