Ron,
you know me, I don't like wrist pins intersecting the oil ring grooves, so my recommendation is 355 cubic inches, which is 4.155" bore & 3.25" stroke.
which heads will depend upon what powerband you want to give this bitchen little motor. I don't keep up with the Windsor world real well, but I would recommend either AFR or Trick Flow heads. Of course, new heads come on the market continuously, and Richard Holdener seems to run the Windsor world, so use whatever he is pushing at the moment! lol.....
George
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