Chris sez:

" It is rewirable for 230 V (see the "Connection: Star/Delta" on the data
plate). There are also six terminals under the cover. I checked before I
hauled it home!"
-- and -- "There's very little corrosion inside the motor and the
windings look clean and undamaged. I haven't measured the insulation
resistance with a multimeter yet, but I thought I'd take a chance on it."

Be careful here. I didn't get the impression it was strappable for 230 -
460 from the pix of the nameplate. "Star/Delta" refers to the way the
windings can be configured for approx. a 1.7 x change in operating voltage.
Generally, a dual voltage motor (one strappable for 230 - 460) has 9 leads
available under the cover. Also, better take it to a motor shop for
insulation verification with a "meggohmmeter". Not something you can do
with an ordinary multimeter.

Bob Swinney