gear size with 408 and 833

Dan, with the 3.09 1st gear, a high "2" number should be fine.....If, it's more of a driver then a hotrod and you have decent vacuum with a "drivable" cam choice. Normally most will use a tire size in the 26/27" max. diameter range on a standard A body, so I think your good there.

The real concern that jumped out at me from the beginning is the 833OD use with the amount of torque that your 4" arm engine is producing. I see no issues in some "spirited" driving, but if you decide to hammer it with some sticky tires.......I wonder about durability? Maybe some others with hands on experience can answer that question.