Butters "Winter Upgrades". . Starting a Little Early

One thing that I really haven't delved into, is should it be on jackstands all 4 on a surface or what.. I've seen people say that it should be level. But what's actually "level" on these cars lol
Around 1/4" or less is ideal. On 4 tall jackstands is how I plan to do it. level should be the F/R cross beams that you are actually welding to.