Okay Daniel, here's the skinny.
Superior used this example on at
least 1959 - 1962 Landaulet models and on removable combinations panels
through 1970 (!). Note center section not as embellished as Crown version. Also, these are
shorter than Crown landau irons (although I don't have one on hand to provide an exact measurement) coinciding with shorter C to D pillar distance.
Next photo shows right '59-'62 Crown landau over right '63-'64 Crown landau.
Multiple subtle differences between them:
'59-'62 are cast bronze. They are straighter. Caps have smooth edges and lower profile (3/8"). Caps are held in by minuscule alum screws on underside. I can't confirm entire castings numbers, nor if those changed between '59-'62, nor can I relay what year mine came off. Only one iron here (right) has a partial casting number ending in _ _ _156. c/c length is 44.75"
'63-'63 are cast pot metal. They have slightly more curve. Caps have knurled edges and taller profile (3/4"), which screw into coach mounting holes themselves. Casting numbers are
LH 254153 G and
RH 254152 G. c/c length is
1/2" longer at 45.25".
Congrats on getting a pair BTW. You know as well as I do that they aren't easy to acquire! If you'd like a mounting template I'll make one. :thumbsup: