As to if bored in back for a manual snout I have a '65 383, a '68 383, a '67 440 and had a '70 440 and '77 440 all were bored to accept a manual.
Respectfully for the cars:
1965 Plymouth Fury III w/ 383 commando
1968 Dodge 2 wd 1/2 T pick up
1967 Imperial Crown Royal
1970 Plymouth Satalite 440 mag w/ slap stick
1977 Chrysler New Yorker Brougham

3 things a man should never borrow: Guns, another mans mopar or his wife.