SCAT stroker cranks, Always like this?

(1) .0015 is OK for a stocker but not OK for a runner (2) I would assume a 408 SB stroker LA engine is a runner not a grocery getter (3) Plastigauge ain't accurate enough for a performance build. The rod journals/bearings are the most critical area with the rotating/reciprocating weights/forces/loading/unloading and is the end of the line in the oil path. Get some quality mikes and some snap gauges & see what you really have there. EDIT You did say 318/390 not 360/408 (which I'm building)