going in circles a little with your question ? interesting mystery on this end. Frustration on your end.
Need to ask -- What?s the basis for thinking that is the right starter and bracket for your motor? I haven?t come up with a model number for a factory electric 25 ('69), so a model number would be good. (Though maybe you are converting a manual start.) I?m thinking maybe there were only kits for 18s and 25s, and no factory start models, but that doesn?t seem quite right either.
Thinking a 33hp starter and bracket (say, '69/?70 or so) might fit your 25(?). Your starter appears to be the one for the ?50s 18s (35s too, I think, with a different bracket). The part number is obsoleted but cross referenced. I?m thinking the 33hp starter might be a little slimmer -- no idea whether the bracket would fit, but can glimpse the 33 bracket in an online parts blowup. The bracket you reference is different from the 33hp for ?69 -- not sure what it fits.