All small block and 63 newer six's transmissions will attach.
That is why they are easy to use. Other than very reliable, powerfull and every junk yard now has them. Oh what fun the general has created!!

Plan to put one in my old six cyl Volvo.

1 1955 Chev one ton. 261 engine

3 1962 Chev c-10 261 engine
4 1966 Plymouth VIP 5.7 GenIII Hemi
5 1966 Imperial Crown Coupe 440 engine