Why dished? Won't it make a hell of a difference just putting domed ones in?
Why polish the rods? Never done that. Making sure they weigh the same is standard bur never heard of polished rods :D
Errrr.....no, you DON'T want dished ones. I'm just saying, that's what came from the factory back in the 70's and it's not good for compression. Sometimes the higher domed pistons a little bit pricey, but I'm sure you can find something reasonable. Polishing the side beams of the rods (I've always heard) helps prevent cracks from forming. Google it.