Yes, there are a few...
In late 1992 Ford built 5 T-Bird with the 5.0L V-8 and a 5-speed manual transmission. They were sold to Boudurant's school in AZ.
These cars were built, then the transmission were installed later.
Keith is correct. No production MN12's carry a V-8 and a manual transmission. That would have hurt Mustang sales.
ALL 4.6L T-Birds and Cougars are equipped with the 4R70W automatic. The SC's '89-'95 have a Mazda manual or the AOD ('89-'93)/4R70W ('94-'95).