Are all small block bellhousings Equal?
 

Well, equal as far as the trans mount pattern goes. I've got a Cleveland mated to an FMX and a C6 sitting on the engine stand. I'm also considering trashing those two and using a late AOD from an F150 (non-electronic). So, if I get a small block AOD trans, will it fit my 351C? And jsut what should I do about the flex plate and torque converter?

The bellhousing will bolt up, and just use a stock or aftermarket AOD torque convertor, it is not engine specific. The flexplate is much harder, as the AOD was not a factory option behinde a Cleveland. What is the stock imbalance on a 351c flexplate? You might be able to swap to a 302 or 351w flywheel depending on the imbalance and the mounting dimensions.

a bit more info on an AOD/351C setup
 

So I found a website with lots of info on AODs and the various engines. Seems that the AOD mated to 164 tooth, 28.2 ounce imbalanced flexplates among others. They even sell an adapter kit for the stock 351C flexplate to the AOD, it only costs $350 (!!!on sale!!!). I'm now on a quest to determine if I really need to get the kit. It includes new fasteners, an adapter fitting for the crankshaft, a few bushings and a very large rectagular plate with the tranny cutout in the middle. It's from CoanRacing.com. (I just looked again, it's back to the regular price of $384.25)

I'm wondering what the rectagular aluminum plate is for. They call it an adapter plate. It looks like a spacer to me, it's about 1/2" thick by the looks of it.

So, now I look for info on flexplates. I saw one tech article from a guy who put an AOD in his 70 something Mustang. The first flexplate he tried didn't work as it didn't locate the TC correctly and it wouldn't interface with the tranny fully. Spewed fluid all over and made a mess when he started it up! Not good.