Done a little research on this and at this point it seems like the best way to do this is to "T" off your fuel line to the carb (or, I guess, the injector(s)) and inject the fuel into the tail pipes using another "T" and the gasoline half of a nitrous oxide injection system. An advantage here is that the N2 O2 "pills" are interchangable and this would allow you to adjust the amount of gasoline sent into the tailpipes. PLEASE don't run huge amounts of gas through your engine using a choke or other method. You'll get what is known as ring wash and ruin it.
To ignite the gasoline I'm thinking you'll need a Ford Model T coil or perhaps one of the control boxes sold for this purpose although I think these boxes cut off the primary electricticy to the car's ignition which of course you don't want to do because if the engine is running you can blow the flames away from your car.
Another factor here is the vortec created at speed behind your car. If you blow fire into this vortec it's going to burn the paint and probably melt your tailights and could even catch your fuel tank on fire - goodby car.
I'm definately going to do this sometime in the near future and any advice or thoughts on this would be greatly apperciated.
Charles F. Smith