41Guy,
The supports (brackets) that bolt to the bell housing are the same, 1937-48 except there is a right and a left.
The book, however, lists the rectangular ones for the convertible 1935-48 and the "W" shaped ones for the others, i.e., 1935-48.
Part numbers from 29-57 book:
Bracket: 594911 L and 594912 R
Cushion: (W type) 756056 L and 756057 R
(Rectangular) 377928 There is no L and R)
I think Steele sells both types as well as do Cof40s and FS. Beware of the rectangular type if they are old. They tend to pull apart relatively easy.
Note: I think both types will fit a 41 so I don't have a clue why the convertible is listed as having a different type. Maybe someone can enlighten me/us.
Good luck,
Charlie
BTW: This topic has been discussed before so... stand by. You may get some reminders.