DE, you "need" a ratio that'll do the job you want to do, you'll never get great gas mileage pushing that brick around with a 327 .... the standard '57 had a 3.90 rear, not bad for general driving, you can haul a load with it - if you're more into highway driving and never use it as a truck, maybe look into Patricks 3.55 rear gear set, or change to a 700R4 to gain overdrive
Bill
