The original Ford alternator was known as a 1G and incorporated an external voltage regulator. The original cars came with either a 42 or 45Amp alternator. Fine for those builds, but replicas and newer technology have much higher current requirements.
The 1G style can be had in a 70Amp version, but that also may be too small. With minor case modifications, the 1G is available in a Hybrid version which will output 100-140Amps – and still use the period correct voltage regulator. Take a look at the Tuff-Stuff site, Ford alternators for various options.
In regards to 1-wire alternators, they just aren’t period correct. They’ll work, and offer some simplicity, but we’re about original.
If you plan to use a hybrid version, be aware you may have to modify the mounting as the case is about 3/4″ deeper.