It should be noted that Ludwig would outfit a kit in any configuration the customer (or music store) requested. The catalogs were just a showpiece for their most common models. Case in point: I have a Ludwig Super Classic kit date-stamped Jun. 1965 (13, 16, 20) that has DUAL 3/4" knob mufflers on both toms, top and bottom (ala Gretsch). Also of note, the bass drum has dual Club Date bass drum spurs - 2 per side (ala Slingerland).
My knob mufflers fit just like Hobb's: they don't lay completely flat against the shell, but rather rest at one end against the re-rings. I suspect this was because the shells were drilled for the baseball bats, which causes the mufflers to sit somewhat higher than normal. Doesn't affect performance at all, though. I've seen 2 other sets exactly like my configuration recently, so I expect it isn't as uncommon as I once thought. Just another Ludwig anomaly.