i don't know...build a 340 to Factory specs including wheels and tires with a 3.23 gear. Stay away from a big cam, gears and tall tires, air gap, converter and all that stuff.
Agreed except the air gap.
Should an OD trans come into play, then it’s multiplying the OD ratio by the gear ratio for the final drive ratio which would allow a change to a deeper gear (numerically lower) while still getting a good final drive ratio. 3.55 X .69 = 2.45, final drive ratio.
3.91 X .69 = 2.69
4.10 X .69 = 2.829 (2.83)