S'up B.W........I put a set of 2.94(?) in the '36. Now the rpms are too low at 60mph in overdrive(1,900 rpm).....that's causing the engine to pull only 14 pounds of vacuum (it should be pulling 18 to 20 pounds for good gas mileage).
I'm going to leave the new gears in it, but now I realize I should have put 3.18(?) gears in it to get the vacuum right. I'll just go to a smaller diameter tire to get the rpm's where they should be(right now, it's got 225/70R/15 street tires on it--that's the max. 27" diameter it will take because of the small wheel openings on the front fenders)
So 3:24 might be perfect for your truck!!
EDIT: the OEM 3:43 gears would spin the tires when the 700R4 shifted into 2nd gear......not anymore with the 2:94's....