3.23's?! Good grief man, you're geared for over 200mph with a .63!
I mean, my tires are 27" tall now so the 4.30's I run aren't quite as extreme a difference on the final drive, but dang! 75mph at 2,500 gets me in enough trouble.
25.6" tall tires so 2000 rpm at 75 mph, perfect for cruising at speed. With EFI I can run at 1400 rpm no problem so any speed over 50 you can run in 6th. This way if/when there is ever power tour or something it'll get good fuel economy and I won't go deaf lol
I'm at 9.59:1 in 1st with the 2.97 first and the 3.23 ring and you're at 11.438 with the 2.66 1st. I don't know about you, but I basically blow the tires off as it is. It might roll out a little better with a 3.55 but nothing to complain about.