Building my 6 bolt need help

[91WhiteTalon]

So I'm planning on building my 6 bolt. Shooting for 800-900hp. I have a magnus 100mm crank picked out and want to run 8.5:1. Just need some recommendations on what bore size, which pistons hold up to good power.

 

[Talyn]

Imo it's best to always go to the minimum bore size, as you can rebuild that block more times. So I would only go .010 if it hasn't been bored. Pistons I think most would be ok, although I believe Weisco's non HD pistons have a reputation of cracking.
If I were doing a build that serious I would probably go with Magnus pistons, they know their way around high HP 4g63s, and besides, you already chose them for your crank, why not the pistons too? . Make sure you have some good strong rods too.