Sure! But, it is about balance. How many big blocks have you seen run twin 850's on a TR?
If so, what was there engine like that it could actually consume/use 1700 cfm?
Your could be right that there to large but it's only 1700 cfms at 1.5" of vacuum. But 2 850 would probably be half or less that vacuum level which probably more like 1000 cfms of actual carburation.
Sale all 3 carbs and the old intake and buy the proper sized DP's.