Found a car for parts...

I stand corrected...I was just looking on BBD and see it might just have a 9 1/4....would this be worth keeping and putting in instead of a 8 3/4?

The 69 440 and 727 will be a good combo for your swap. The New Yorker's oil pan will probably be the correct 187 pan for the swap. The 8 3/4 rear (and yes there is a 99 percent chance it WILL be an 8 3/4) will be way too wide for an A body. After you pull the drivetrain, put the rest of the car on Ebay. You might get a few hundred for it.