M & W Traditional Outside Micrometer (1966 Series) - Are Anvils Interchangable ?

[EddyCurr]

An incomplete 2"-to-6" Moore & Wright Traditional Outside Micrometer
With Interchangeable Anvils (1966 Series) was included amongst some
instruments I bought the other day. Three anvils (2", 4" & 5") are missing
from the set, along with one setting rod (2").

Are anvils from M&W outside micrometers of the 1966 series interchangeable?
If they are, this would broaden the selection of used sets to choose
from if I attempt to complete my set.

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