Mike: No, you're not forgetting anything. However, it would be great if we could obtain a set of LB instructions for their 2B interior kit and compare it to their 2A kit as described below.
When I ordered the LB complete interior 2A kit in 1982, for my solid front seat 5 window coupe (Model 01A-77B) with package tray, the price was less than the LB interior kit for the 1940 Business Coupe, Model 01A-67B that had the small "opera seats".
I think I paid a total of about $550 back in 1982. Perhaps the photos below will be of some help. I hope a Fordbarner owning a coupe Model 01A-67B will post clarifying photos to clarify what the 2B kit installation looks like.
I still have the LB instructions from when my 2A kit when it arrived in 1982.
Notice LB lists the two interior kits separately with the Business Coupe interior costing more.
Photo 1: Notice kits are labeled as 2A and 2B, (indicating there is a difference between the two?).
Photo 2: The 2A kit is for my car Model 01A-77B with package tray and no split front seat. The 2B kit is for the Business coupe with split front seat and "opera seats". As has been pointed out many times before, Ford Motor Company never officially named any coupe an opera coupe.
Photo 3: LB pictorial
Photo 4: LB pictorial showing 2 differing pictorials.
Photo 5: LB letter explaining vinyl pebble grained package tray covering use. Vinyl cloth was developed in the 1920's so it would be interesting to know if Henry Ford or his vendors ever used it in for covering package shelf interiors.
If you have an OEM stock 40 please post photos of what's behind the front split seats.