Starter Motor Numbers/Types

[Klaus Schlueter]

Hi all,
Does someone know wether there are different LUCAS-types of starter motors for the Stag?

--In my ROM the no. is Lucas 25627 (1974 Stag).
--In my loft I have 2 old units with 25648 (don't know wether they fit,but look alike).
--on ebay was an offer with 25687

Do they all fit any Stag model year and are there even further types/numbers? And if so, what is the difference?

Any help?

Klaus