Here's another option... return the 1406, and use the money saved on a rebuild of your quadrajet. Then, you won't have to buy an intake, fuel line, kickdown adapter, etc. The quadrajet is a very very good carb. Excellent off idle driveability, decent mileage on the small primaries, and big old secondaries for having fun. I can say this with no bias, my 65 has a 4GC, and my 71 has an Edelbrock 1405 (but used to be 2GC).
I'll add one final point: if a tech can't make a fuel line from a pump to a carb on a SBC... you need to be looking for a different mechanic.
Two doors, four doors, wagons, and ragtops.