Upright, well padded.
I'm just about to strip the car down for a full respray and wanted to know what other have done as far as the right way to store the windscreen.
Even a very slight point pressure will crack it.
(long winded geezer rant below, you've been warned...)
I pulled the new glass from my tii once, and a ham fisted friend who was eagerly trying to learn and help (eg getting in the way) offered to take it and set it down. I had a thick pad along a wall for it but he put it down on the bare concrete adjacent to the pad. As luck would have it, he set the edge down on a very small pebble and ... Craaack the window was junk. Good thing my deductible was only $300. Once a friend helped me check valve clearances on a head on my work bench ... Eg without the intake and exhaust cams connected by the timing chain "I'll just rotate the cam and write down all you clearances, starting with the intake side."
Needless to say I rarely let friend help out anymore. Can't afford the cost in parts or the liability.