I just did the swap and you can use the 94 trans if you have the bellhousing for it. The input shaft is longer but if you use the 94 bellhousing youll be fine because it is taller than the fox body bell. Also depending on the year of your car you may have to get a different starter. I got one for a 92 stang and it worked great, I just had to run an extra wire.
yeah yu can get the sn95 bellhousing, but imo its easier and cost the same to just change out the input shaft and retainer sleeve so you can reuse all the stuff you already have. just watch out for the needle bearings when changing the input shaft.