Transmission help

Well i been doing some researching about switching to an automatic. I was planning on a aode/aod/4r70w(v6) and putting the wideband 4r70w wideband internals in it, I was a lil curious does it make a differnece to which casing I get? And i was goign to go with a 3200 converter, Lentech Manual Valve body, Hardern input shaft, the 4r70w internals, tranny cooler, deep sunk pan, alum driveshaft, and i think thats about it.


Can i also make the overdrive a switch since im going to manual valve body? And does anyone have a manual one in one of those trans how do you like it? Also will i be dissapointed with that im in the state of getting AFR 185's, 150 dry kit, and the mods in sig and not sure about my t-5 life, Can i still hit low 12's or a 11.9 on motor with e/t streets with a limited amount on suspension...then maybe high 10's on nitrous?

And anything else i need to get? thanks
 
i know this is a really newb question but i dont think my t-5 is goign to last.

Im just confuse when i hear people using the aod and trans out the v6 mustang they just use the case is there a difference? and a lil curiuos on the aode with manual valve body i have friensd with c4's and them but it would be with 4 gears not 3 and then it would have a overdrive right? Need some opinions thanks