To determine how much alternator you need, you just need to total your current draw. I think you will be amazed at how little you have added.
The head lights you put in draw less current than the old tungsten lamps the car came with. The air only draws 7 amps more than the heater. The stereo is probably fused at 15 amps and draws about half that. The fuel pump if it is a Holley or a Carter draws 2 amps. The relays that run your headlights will be another amp or so. The only thing I dont have a feel for would be the radiator fans. I would have to look that up.
If you keep the battery trickle charged or battery removed when the car is long term storage, the total current draw will be in the 35 amp range with everything on. The only heavy lifting the alternator does is recover from a low or dead battery. That is why it is always better to charge a battery rather than jump it. Since your removed your ammeter, you will not know when the battery is drawing heavy current charging up.

Craig