Ok you ask .
From what I've read you can use any auto trans that fits a sbf , same with a straight shift bellhouseing . I think you can use a sbf flywheel or flex plate for a zero balance eng. Me I'm planning on useing a 2000 Mustang 4R70W trans off a 3.8. V6. To get there I'm going to use a 300 flex plate so my torque convertor bolts up . It will need a stand alone trans controller & a tps to operate the trans .
I have read you can use Maverick 250 mounts in a Mustang but have to drill a hole or 2 in the frame. I'm looking for a member on the Vintage 6 facebook forum who makes & sells mounts for this . The eng is taller & the stock mounts push it up too far , & even with the correct mounts a carb hat may have to be used to have hood cleareance .
The eng is also longer which with sitting higher means loose the stock fan & run a pusher elec fan because the water pump sits pretty close to the radiator ..
It all works out for me because I was planning an explorer rear end swap somewhere in the install of my alumn head,cam,& roller rockers on my 200 . My car The Money pit has been sitting in the shop 2 months after I installed a Hyper Spark dist so the Sniper could control timeing .& during this time all the trans fluid has leaked out I think maybe thru a pourus alum trans pan . For me it been a 3 year accumilation of parts for 3 different cars . My 250 is coming out of a 69 Ranchero I was going to work on but it's now a parts donner .
If you wind up doing the 250 swap you should give serious thought to a 2300 Sniper on it , my 200 runs like a different car after I put the 2300 on it .
If you find anything on this swap you think might be useful to me let me know . Good luck