I have a D16Y7 that I plan on putting a Y8 head on. But I have sent the block to a machine shop to have the cylinders bored over from 75.00 mm to 76.00 mm. What else would I have to change for the engine for everything to work. I've already got the pistons and rods (they are forged).

 

I believe that the maximum allowable bore for the stock engine cylinder is only 0.5-mm not 1-mm.

 

OP, you "can" typically get away with a 76mm bore size IF you stay naturally aspirated. Honda's recommendations are a bit more conservative... and not driven by the limits of the strength of the thin steel liner, but in fact, stated because no OE head gasket is offered that would safely work with a piston larger than .5mm over-sized.

The steel will certainly be weaker, so a quality tune, with conservative ignition timing to help it survive long term, is a must.