The original owner in 1940:

How it was determined that the car pictured is 56-45:
The Assembly Plant Record for 56-45 indicates the Sales Branch was Richmond, CA, the car was shipped to Jacksonville, FL, the color was Monterrey Blue Iridescent, and the leather was red.
The photo caption lists the dealer as John H. Eagal, Co of Stockton, C, which was served by Richmond, states the Peffers drove their car back from Florida, and the car is described as “Royal Blue” with red leather. Additionally, only two 1940 Cabriolets were painted a special blue with red leather. The other was 56-255 which was purchased by Xavier Cugat.

Car description from the Richard H. Dreihaus Collection:

Photos of the car from 2023:

Miscellaneous photo:

Correspondence between June Davis of the LCOC and Dave Cole in November 1986: