having a brain fart here. help me with this excerpt from his wheel building page on an improvised wheel dishing tool:

"... You may also check dishing by placing two piles of blocks ... on a tabletop to support the rim at two places opposite one another. The distance from the tabletop to the hub locknut on the underside should be the same, no matter which side of the wheel is down."

so let's say there's more space between drive-side locknut and table compared to the nds. which side do i tighten?

if the difference is 4mm (meaning an error of 2mm), do you try to true this slight error away? how much does it normally take to move a rim 2mm to one side? a half turn on each spoke on that side? what's a reasonable length in dishing error to leave in place?