I have been having a problem with gasoline fumes comming from the carburator area after I have been driving then turning the vette off. About 5 to 10 minutes later strong gasoline fumes are present which continue for about 3 days.   I have replaced all fuel lines, gas cap, vapor canister, carburator with a rebuilt unit, fuel pump and checked all lines for any leaks. I also noticed that the inside of the intake manifold is wet with gasoline fumes after  the engine is turned off.  After the vette is shut down for about 3 days the fumes stop.  I have had the engine tuned and the compression checked and everything appears to be good.  Note: The carburator is a Rochester Quad 4. 

You may be smelling fumes from the charcoal canister, under the driver side fender. It may be saturated with raw gas. That's one thing to check. The canister can be replaced, if needed.
Are you sure the fumes are coming from under the hood? A leak at the rear of the car will smell just as bad as one in the front. Check ALL of the lines going to/from the fuel tank, both on the driver side and passenger side of the car. The lines on the driver side are the fuel vapor lines...they go to/from the fuel tank to the canister. A leak in any of those hoses will give you a raw fuel smell, also.

If yo are seeing raw fuel puddling in the intake after shutting the engine down, your float level may be too high, or the car is getting so hot the fuel is percolating in the bowl, and running out into the intake.

I had a similar problem a couple years ago.

I would not recommend using a match !!  lol

Mine had the strong gasoline smell also and like the response above it turned out to be weeping out of the fuel pump. New fuel pump, no more smell!