Since GM used the same block for both the 230 and 250, the difference being the stroke and piston, the only visual identification is the top of the piston.
The usual practice before ordering parts is to tear down the motor. Unless you know the history on the motor there is no way to know if there is a major problem with out tearing it down. A major problem would be a broken piston ring that has scored the cylinder so bad it can't bored over sized and requires a sleeve. Bearings for the crank are another item that until the machine shop has ground the crank and eliminated the wear you don't know what size is required.
There is also another engine code that seems to have been overlooked. That code is stamped stamped on the distributor pad. That code still won't eliminate the possibility that someone hasn't rebuilt a 230 into a 250.
Another consideration is the class rules that you will be running your altered in. If you looking to be competitive what will the rules allow. The 292 six used a larger 1bbl carb and exhaust manifold.
btw the preferred method to posting pics is to post the link only.
Larry
