Mac Shops had three different extrusions. All had the same roof pattern for corrugations. His first was as above on those beautiful B&O cars. Then he did the Zephyr pattern - identical, but the roof corrugation pattern extended through the letterboard area above the windows.
The third pattern had a slab side below the windows, matching some PRR coaches and most dome cars. I have a photo somewhere of that.
K-Line also made fairly accurate Budd cars. I have one Zephyr car that, while quite shiny, matches the Mac and GG Budd cars.
Clark Benson bought extrusions made with the inaccurate Lionel die. At the time Lionel had a correct die, and used it to make baggage cars with strange doors. Had Clark used that die, he would have captured the 2-rail market and Haynes MacDaniel probably wouldn't have bothered.