I bought a drivers side outlet WP housing a couple of years ago and the t-stat outlet fit fine.
I am in the process of intalling a 440 in a 66 Coronet as we speak...using a pasenger side outlet
440 source housing this time...guess what...stupid bolt holes are too close on this one Im using a thicker flange t-stat housing, so the hole elongating process is S L O W
Brandon fix your stuff!