My 292 was bored back decades ago.  It is slightly bigger than 292.  How much I don't know.  My current carburetor is an 1850-1.  That is the right number for a 600CFM carb.  That isn't the recommended CFM for a 292 which is more 350-400CFM.  Further I have the intake manifold of a 1957 Tbird.  I own the correct manifold and carb for the 1955 Tbird, So, I'm sitting here needing a carburetor overhaul of the 1850-1 (not correct for the Tbird).  The fuel lines are set up for it, but I'm wondering if I wouldn't be better off to get the carb for the 57 Tbird.  However, it is designed for the 312, not the 292.  I'm resurrecting this car from my high school days.  It won't be a show car, it will be a short haul driver.  Still, I'd like it to look nice.  I thought I'd drain the brain power on this site for some suggestions.  The 57 manifold with the 1850-1 won't let the hood close on the correct air filter, duh.  The cheapest route seems to be the 1850-1 rebuild, though I have a shot at a 1273 for the exact manifold (though it is for an automatic 312, not a standard 292).  It's that the fuel line receptacle don't match on the 1273 that is slowing me down.  I won't even go into the choke.  I'll settle for manual.  Finally, Tbird manuals distinguish between a carb for an automatic versus a carb for a manual tranny.  How bid a deal is that?

Sorry I made this so complex.  I didn't know the manifold didn't match when I got the car 54 years ago.  Likely some kid was trying to make his 55 bird faster.  Dropping a 289 would have done that better and more effectively than swapping manifolds and carburetors. 
Thanks