Classic/Antique Car Repair: New Problem, fuel leaks, headders

Question
Roger,
I have encountered a new problem.  I was out on the road the other day and the alternator light came on as I was driving down the highway.  Now, if I sit in the car with the car idling, the light stays off.  When I push on the gas pedal, the light stays on until the car drops down below a certain RPM.  The car just all of the sudden started doing this the other day.  It never did this before.  My guess is that the alternator has started going bad and cannot keep the battery charged.  Is this correct?
Thanks for the advice in advance,

Nate
-------------------------------------------
The text above is a follow-up to ...

-----Question-----
Sir, I recently had a 1967 ford fairlane restored "professionally" (I am unhappy with the company, but that is another story) and I have a strong odor of gas inside the car.  So bad in fact that it gets in my clothing making me smell like exhaust for hours.  I have visually inspected the fuel tank (which is brand new) and worked my way back under the car to the engine.  I am not seeing any fuel leaks or wet spots.  I wonder if you can give me some advice.  I have been told..."old cars are supposed to smell like that."  But I don't believe this.
The engine is a 289 block bored out to a 302 with an aftermarket edelbrock 4 barrel carburator.  Duel exhaust w/ headers and flowmaster exhaust attached.  C-4 transmission with a shift kit added.  Power steering was also added after market.  Any help would be great!
-----Answer-----
Nate;
Hi , well it might be the ex. system in the back , if it is not far enough you might have the fumes comming into the car, and when you start to make a hot rod, and with the headders and etc. you can get some smell, but not that bad, if you do not see any type of fuel any place than it must be the  ex. or check the headder gaskets, if you have no gaskets  than thats why. also tighten up the headders where they bolt on to the heads too.

Answer
Nate;
   Hi   well if the pipes are at the rear tires than you are smelling the ex. fumes as they are comming into the car , my 396 SS did that when I had short pipes, it will make you feel sick or put you to sleep ,I would run them up and over the rear end, as it is illegal in most states to have them short , you might get away with some flex pipe that would be the cheepest and easy way to go about it.  ok