We made a cabinet long ago to dry our coated 18X21" Newmans and
when the auto came along just slid the 23X31" in on about an angle of 20˚
because of width being too narrow.
Never seen a difference with even that kind of angle.
Not optimal, but I'd say
surface tension of emulsions viscosity is enough to over come any ill effect.
Hope your floor isn't that much off.
How about propping up rack to make level...