Replacing an SP auto car in my freight car fleet

I have written in a number of previous posts about the process I follow in upgrading the overall fleet of freight car on my layout, both in terms of improving existing models, and in other cases, replacing models with better alternatives. My most recent post about this, which includes links to earlier posts, is at this link: http://modelingthesp.blogspot.com/2013/10/evaluating-freight-car-fleet-upgrade.html . In the present post, I give another example.
     After World War II, Southern Pacific bought its last class of 40-foot automobile cars, Class A-50-16. Delivered in November and December of 1947, these had modern (Improved Dreadnaught or ID) ends and wide double doors, and were numbered 66175–66674. For a number of years there was no easy way to model the basic body, and instead I assembled a stand-in, using the old McKean double-door car body. The model really depicts a later car, with a later design of ID end, what is called a 1+3/4 end. That means two end panels, the upper with three major ribs, the lower with four, and the “1” refers to a different kind of rib at the top of the upper panel, rectangular in this case. The model also has a diagonal-panel roof, whereas the SP cars had straight-panel roofs.
     [There is an error about these cars in Table 7-1 of my Volume 3 (in the series Southern Pacific Freight Cars), where Class A-50-16 cars are described  as having diagonal-panel roofs, though photo captions in the same chapter correctly identify the A-50-16 roofs as straight-panel.]
     As just mentioned, I used the McKean model to represent a car of SP Class A-50-16. I did modify the side sill profile to match Class A-50-16, but the glaring discrepancy (beyond the already-mentioned ends and roof) is that the car has 6-foot wide doors, whereas the prototype doors were each 7 feet, 3 inches wide. A couple of scale feet may not sound like much, but on a relatively short car like this, the proportions of the doors and car side are quite visibly affected. Here is that model:

This image, taken from an old slide, makes the car look closer to brown than boxcar red, but the model in fact is really boxcar red. And yes, that stock car to the right, lettered for California Livestock Dispatch, does not represent a real owner.
     Sunshine Models offered a kit for some years for a correct model of SP’s Class A-50-16, with correct 4/4 ID end, straight-panel roof, and 7-foot doors (kit 40.2). Recently I arranged to have Dennis Williams build and paint one for me, and I applied decals and weathering. It is shown here in front of the Shumala depot.

     The older model car, the McKean stand-in, will be sold, and only the new and correct model will grace my occasional operation of a cut of cars carrying auto parts and automobiles along the SP Coast Line on my layout.
Tony Thompson