Stop. Before you drill into the fuel cap, maybe remove the fuel sender, pour in some fuel and reinstall it. You haven't found the keys in the garage, could it be in the house on the key holder, or wherever you put your car keys, or someplace else? And welcome back Sopp I remember your interesting build.
I would jump the red wire with the green wire and see if it starts.
What do you mean by jumping the red wire with the blue and green? The grey/blue (grey with a blue stripe) is supposed to supply power to the ignition, not receive it, so don't connect that to the red wire. Or do you mean the green wire with a blue stripe, because that wire is supposed to be for the light switch. The blue stripe might be faint now after all these years, so is easy to confuse with the green wire for the ignition switch, and my eyes are over sixty years old as well.