273 Engine _ Need ID of Intake
You should be able to buy a "straight through" adapter for that manifold. They have the narrow and wide mounting holes. Assuming your carb is "narrow" and the intake is "wide", you would remove the intake studs
You would install 4 bolts (hex cap screws) with threads sticking UP into the adapter.
Install the adapter onto the manifold with a gasket, and the SUPPLIED SCREW HEAD bolts which fit into recesses in the one set of holes on the adapter.
Then put a second gasket on top and install the carb. These adapters have "hex" sockets on the bottom of the bolt holes to capture the bolts sticking up, and on the top side, a slight recess in the TOP of the bolt hole so that you can install a short head screw in there and end up flush with the top of the adapter
I don't know who made this adapter, but you can see the recess in the top holes:
Below is the wrong adapter, but shows the hardware. This particular adapter is threaded for the studs. On other types of adatpers, you put the special "low nuts" on the studs, and insert them from the bottom of the adapter. The nuts are captured in the hex molded into the bottom of the holes, and the slot head screws hold the plate down on the manifold
Obviously, this is not needed on modern Carter/ Edelbrock carbs with the two sets of bolt holes
You should be able to buy a "straight through" adapter for that manifold. They have the narrow and wide mounting holes. Assuming your carb is "narrow" and the intake is "wide", you would remove the intake studs
You would install 4 bolts (hex cap screws) with threads sticking UP into the adapter.
Install the adapter onto the manifold with a gasket, and the SUPPLIED SCREW HEAD bolts which fit into recesses in the one set of holes on the adapter.
Then put a second gasket on top and install the carb. These adapters have "hex" sockets on the bottom of the bolt holes to capture the bolts sticking up, and on the top side, a slight recess in the TOP of the bolt hole so that you can install a short head screw in there and end up flush with the top of the adapter
I don't know who made this adapter, but you can see the recess in the top holes:
Below is the wrong adapter, but shows the hardware. This particular adapter is threaded for the studs. On other types of adatpers, you put the special "low nuts" on the studs, and insert them from the bottom of the adapter. The nuts are captured in the hex molded into the bottom of the holes, and the slot head screws hold the plate down on the manifold
Obviously, this is not needed on modern Carter/ Edelbrock carbs with the two sets of bolt holes