Brookwood wasn't the Impala of the wagons. Put in to perspective, DelRay was the basic utility/sedan delivery wagon, Yeoman was the Biscayne, Brookwood was the low end BelAir, Parkwood was the high end BelAir and Nomad was the Impala.
Added later. I'm pretty sure that floor shift wasn't available until 61', especially in a wagon. The car most likely didn't come with a 348 either, but it was optional. A factory 3-2 setup for that year was more rare then than it is now.