it will work but thats alot of torque for an Alpha in a 35 foot boat. It dosent make much sense to put a bunch more power in it if you have to baby it, I would freshen up the 454's and maybe bump the cams a bit. Those engines have cast internals so you dont want to get to crazy. The Aplhas will thank you for it later
have you ever thought about upgrading to Bravos?