I am glad you got it all together.
The bulb was the only one I could find in a 12V that would fit the socket. Its likely just a side marker bulb. I had no intentions of driving at night but wanted to try to be somewhat legal to ride around town.
If you look through all that stuff I gave you, there is a bag of red fabric covered wire. You should use it for the headlamp.
I wish I didn't lose interest in this bike. But, I used the funds to buy a fishing boat and have used it 100 times more than I rode the bike.