100 amps might be a bit overkill depending on what additonal accessories you plan on running.

when you say restoration, do you mean that, where everything should look stock?
or resto mod, where as long as it is close you are happy?

because those things make a difference in how much you can upgrade.

the mad bypass "looks" fairly stock, but higher than 100 amp alts don't really look stock.
78 amps is the highest "stock" square back you can get from a parts store with life time warranties.
there are kits and powermaster alts that go to 100 amps ish for the square and round backs.

then there are the later denso alts from toyota's and pre magnum trucks.

but really unless you are running electric fan's, fuel pump and a few other things that are high amp draw's do you really need it?
what are you trying to fix?