I can say from experience that the engine dolly for the 235 will NOT fit the 250/292s! The later engines are not a straight line down the passengers side. Neither will the 250/292s fit a SBC dolly without modification. I've done both, and they are just for moving engines around or storage.
I like Woody's idea, but how will you get the engine/tranny combo over the front cross member without a hoist?
Best wishes,
Les