A AA/FD is scratching for traction all the way down the strip. While 160 is a commendable speed for a stock bodied car, I doubt if you're breaking traction as you go through the traps. And, it is only at the top end that the wing will help at all. Also, the aero forces are proportional to the SQUARE of the speed. In other words, the force at 160 will only be a quarter of that at 320.
Sorry to be so pessimistic, but I think you can spend your time and money more profitably.
As an aside, I think it's time for the AA/FD crowd to start considering a full bodied car with a second engine to suck the air out from the underside. Or, has the NHRA foreseen this and banned it? That would be typical of their stand against improvisation.