Machining a Piston from a Casting

[hermetic]

I have been pondering this, and trying to work out why this process, which has been done millions of times in industry is so hard in this case, and I think it is perhaps the casting should have had a core in it to give the gudgeon pin bosses a position on the outside of the piston. would it be possible to make a vee block to fit inside the piston and on to the gudgeon pin bosses, but also bee deep enough to fit the lower half of the block in a machine vice, clamp in position on the piston crown, and drill and line bore. Best done on a horizontal boring machine, but maybe possible on a lathe with sufficient centre height. I am intigued, what is the bike?
Phil