I can't disagree if those are yours and 1Wild's findings. That has not been mine. typically decks are .020-.030 taller than factory blueprint, and if they are milled on a horizontal milling table with the typical multi cutter round head (like the factory) they will be out a couple thou from valley to exterior edge just because of the curve of the wheel, possibly more depending on how the block is held to the table, the quality of the lelvel used to set it up, and the attitude of the machinist.