Ok I think I might have the answer for you...
I'm betting it's not .006 it's .060 and unless you bought the sleeves to match it will not fit.
I've never heard of pistons only being oversized by 6 One Thousandths.
But 60 One thousandths, yes.
How did you determine that you needed oversized pistons?
If it's a Kubota tractor it's a Kubota engine, look on the side of the block right behind the injection pump and hydraulic pump there will be the cast in CC's of the motor, it should read 1115cc.