R-Fast
What version of Bluebird have you got as a donor?
According to my book, the wagon that came with the four speed had the H190 diff, while everything else had the H165.
Perhaps you and Woody should swap diffs.

P.S. My parts book says that the H190 that was used in series 1 & 2 Bluebird wagons is 3.889 to 1 ratio.

Most of the H165 diffs that were used in all the other Bluebird variants used a 3.9 to 1 ratio, EXCEPT, for the four speed sedan, which used a H165 with a 3.7 to 1 ratio