This same topic was recently brought up on the inliner's board. The suggestion there was to look in a spark plug hole at the piston top...If dished it's a 250.
Yup, thats about the only way without tearing into it to tell... when you run the codes, they come back as a 230/250... doesn't specify which as both used the same block... just internal differences, as far as I know at least
