I know this is an old thread, but just for future reference.
The trans is the same as any other early C6 except, the case, tailhousing and output shaft are unique. Case for bolt pattern, tailhousing for mount and three spline yolk with linear bearings.
The tailhousing and output are a direct swap to any other C6.
Also original lincoln forward clutch friction plates are a coarse spline as are other early C6 units. This is easily updated to the later fine spline by using a later input planet internal gear.
1958 Mercury Monterey, 430 400Hp Super Marauder
1960 Lincoln Continental
1964 Mercury Marauder 427 425HP
1963 Galaxie 2 door sedan 427 425HP
1963 Galaxie 500XL 390 300HP
1951 F1 Gasser
1958 Mercury Monterey 430 Supercharged (project)