The AOD is an easy bolt-on to a 250. Use a 164tooth flexplate from a 300 and it just bolts on.
The only hard part is the Throttle valve linkage. You need to fabricate a rod or a cable to activate the valve, otherwise it won't shift properly and could cause the trans.
The AOD wor to failh the .6ks nicely on the 250 wit3 OD. It has a reputation as a power pig, but with a direct drive 4th gear it is actually pretty efficient.
There is no easy way to use an AOD on a 200. It may be possible to use a C5 bellhousing on the A4LD transmission, but no one has tried that to my knowledge.