Almost forgot to post the final result.  I have found that I have an entire 88 engine (1949 vintage) in my 77 (1950 vintage).  That explains a lot about how "crowded" the bell housing area is, and the minor alterations of battery tray, etc.

Anyway, the Zenith works OK.  Doesn't seem to have lost any power (but running a 7' bush hog isn't exactly much of a chore for it and that's all that is needed this time of year).  Picked up a kit for the MS 374 and will rebuild the MS carb when I get a round tuit.

Meanwhile I've picked up a '63 550D with 588 Loader and have been pulling the routine maintenance on it (fluids, PTO seal, filters, cleaning years of grunge off, etc.).  Power steering makes a world of difference!

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