Have you already bought your pistons? The efficient way to restore the bores in 615 through 617 engines is to buy oversize pistons and rebore the existing sleeves oversize. If you come to a cylinder that doesn't clear with the .5mm overbore then put a sleeve in that hole and bore it to the oversize piston. The sleeves have to be bored to get them out and the new ones have to be bored and honed after installation. The sleeve could care less what size you bore it to.
The straight boring job is a third or less of the boring and sleeving operation and you don't have to buy sleeves. There is no down side.
Bosch Master, ASE Master, L1
33 years MB technician