Technical To AOD or not to AOD

I have a 302 and AOD in my '65 Ranchero with 3:55's in the 8 inch rear, 225/60 15's. 'Tis a minty combo.

 

minty?

 

I've used the AOD in a couple of classic Mustangs. The first car had a 2.79 gear and a 289. It was a dog. With that rear gear both first and OD were way too steep. Take off was sluggish and the engine struggled at anything under 75 in OD with rpm just too low to let the engine make any power. At 70 mph it was turning way less than 2000.
The other car had a 302 and a 3.73 gear. That was a good combo. That gear added about 700 rpm to the equation and gave me decent acceleration and a nice high speed cruise rpm of about 2500 @ 75.
The throttle valve adjustment is critical.

 

Check what the gear ratios are in both transmissions. Many overdrive transmissions actually have a lower first gear than some of the non-OD transmissions, so you may gain some acceleration. Also compare 2nd gear ratios.
If after converting to OD you find your engine struggling to use OD, then put a different rear gear in it and gain some more acceleration. Didn't see any mention of the year of the vehicle, but if it has a 9" rear you can shop around till you find a slightly higher numerical gear and then resell your old pumpkin for most of what you gave for the other one.