Slow and steady wins the build.
I do believe that Packard used the BW T85. There is no stronger 3 speed OD and very few period stick trannys that can match it. If you are not into "old school" or not seeking an edge in a vintage racing class the whole Packard 8 choice seems to be folly. The T85 would be a kick to drive.
If you are bound to set this engine up against the performance of modern engines I don't think you will ever meet this goal ,"It will be in the 52 Packard club coup it came in. I would like to street drive it and I plan to do so rather often, i wont say every day but a few times a week for sure." If you have deep pockets and want to thumb your nose at a few V8s go for it.
