A progressive two barrel will not work on its own, you need two of them. One is just to small for the 235. This is why they work so good in dual setups.
Unless the the carb has a direct hole in the casting letting fuel out, it can be rebuilt and made to run pretty decent. Any fuel running down the sides or out the shafts is from overflow or leaking gaskets.
First thing to do is add a small fuel filter right at the carb inlet. Then open the top and remove any trash that you see. Look under the needle valve and flush the area. Check the float for leaks and be sure it floats, replace it if in doubt.
Find another carb mechanic.
Joe
