I have the Weber 38DGAS 2 BBL carb on my car. If you are running the stock, unmodified head with the integral fuel log, Clifford has a kit that includes the carb, mounting adapter, and linkage adapters. It has everything that you would need.
If you are running, let's say an Aussie head, the kits from Clifford are of no use. You would need a machine shop to build you an adapter to fit the Aussi intake bolt patern. You will also need to go with a throttle cable set up and possibly a new gas pedal. I have some experience in this area, since I just converted everything over. I went with Lokar parts instead of using parts from a salvage yard. It costs more, but works really nicely. If you are interested in any of my conversion, I can send you the part numbers for everything and pictures.