I have to have my 77 Powerwagon smogged. It is originally a 318 2bbl engine. I currently run a 4bbl manifold w/fuel injection. Even though my engine runs CLEANER with the fuel injection I can't pass the visual inspection. I have a 2bbl intake from a 1965 273 engine. Any drawbacks bolting this onto the 318 so I can temporarily run the stock 2bbl carb? If I recall correctly it's the same manifold dimensions for 273/318/340 but it's been so long I wanted to confirm this.