The 292 is taller than the 250, you will need a longer exhaust bellows from the elbow to teh exhaust pipe. Way back when, I wanted to swap in a 292 and use a four barrel Q-J on it(the factory intake will accept it if you pull the adapter plate off). cam shaft might be a bit different, but first of all, make sure the motor is worth messing with, they haven't made them in quite a while