Flooding problem on B&S Flo-Jet carb

I am pulling my hair out ! I have just rebuilt a 1960 B&S 3HP Model 80331 engine that powers a Pegson Marlow Pump.

I have replaced the points, coil, piston rings, main bearing, fuel tank and fitted a carburettor rebuild kit including new float needle and jet etc. The float height is correct, but I cannot get her to start. Fuel is dripping out the bottom of the carb and oozing through the gasket (also new) between the top and bottom of the carb.

I feel like taking the whole lot to the tip except I have spent far too much money already !

One thing I have just found out; the carburettor listed in the B&S parts list for my engine type says, Kerosene ??

Any suggestions gratefully received.