A V8, 4 barrel, 4.57, and anything over about 45 mph means the secondaries come open and the mpg goes from about what the 292 will get to half. One of the few advantages six is that everybody wants a V8. Patience and luck could get a decent 292 for less than half the cost of a V8, because someone replaced it with a V8. The exception might be he 292, but with luck.
Wrenchbender, left out the motor mount tower on the passenger side. The fuel is in the middle of the engine and the tower was moved back. I have one that is a little rusty you can have for the ride. Also the carb will be under size. The 230 carb has about 1 9/16 throttle bore and 292 is 1 3/4.
You haven't mentioned what tranny you have. I'm guessing it's sm420 with granny first. It will be fine with the 292. If you have the emergency brake lever on the floor next to the shift lever. The replacement tranny will have to have the emergency brake on it too. Or find an under dash lever, rear axle backing plates with emergency brake cables and everything in between.
Larry
