I second what Gerardo said. Since your Grizz is pretty much center shot, you will do better by going with a heavier spine on broadheads. 60 to 65 should be about right with 125grns up front. If you go for a heavier head like a 150gr, bump it up to 65-70.
Also second the Surewood Shafts. They come incredibly straight for woodies, and are very tough. For someone who is switching over to woodies, this will be the path of least resistance and best results. Not much (if any) staightening is needed for these shafts. I've been making woodies for 28 years now - since I was 15. Wow, I'm getting ooollllddd.