Hi, I just swapped a Magnum Viper T56, 6 speed into my '65 as well. I have the close ratio you show in your post. I also have 3:08 gear in my rear end, ordered 4:10 gears to replace the 3:08's. Still waiting for the gears to come in, as they are not a stocked item for a Pontiac rear. I did drive the car one day with the 3:08's, before I put it into winter storage. The T56 was nice but the 5th and 6th shift I couldn't used because of the low rear gear. Even with that I was still able to smoke the tires. Hope this helps with your decision.

Joe.

 

Joe,
Thanks for your feedback and good luck with your new gears! In the end if my T56 choice doesn't wow me off the line, changing gears would probably be my next step. Although a nitrous bottle has me intrigued, but that may be over the top?
Noangelbuddy