I shoot the Hammerhead out of my 62-63# @31" bows. I haven't found the need to bareshaft them at all. The broadheads hit right with the field points, and that's all I'm really concerned with. They are very tolerable of point weight and I can shoot 125 to 200 grain points out of them.
The weight on mine with a standard insert, a cap wrap and 4x4 fletching is 500 grains (with no point). I imagine that if you cut them to 29", they'll weigh around 450 grains, but you'd probably need to go with a 200 grain head (at least) and need to use the 100 grain brass insert. You'll then be around 750 grains.
If you want to keep the weight around 600, you'll need to go with the Lites, or maybe even go with the regular Trad or even the Trad Lites. It might be worth it to get a test kit of the different AD shafts from 3 Rivers. I'd get that before I started cutting the shafts you have. You'll have a lot easier time selling the Hammerheads full length than you will if you cut them to 29".