It sounds like you are on the right path to getting your motorized bicycle started. I have been trying to find a way to put some lights on my bike and the best thing I have come across is using a power wheel battery and a fog lamp for a car. The battery weighs about 5 lbs and is mounted in a zip up cooler type lunch bag on my carrier over the rear wheel. I have a small red trailer light I mounted to the rear reflector you can find the lights the wiring, switch, etc. at any auto parts store or wally world for around $15.00. You can use virtually and rechargeable battery you can find but this is where I got mine.
ESR 750 electric scooter - Go-ped - Electric Bike or Scooter - Batteries Plus
You don't have to use these batteries but you get the picture. It works as good if not better than the $200.00 lights.
Or if you are a DIY type guy you could try one of these
BIKE LIGHT "Commuter" under 5 bucks By Veggiecycle
BIKE LIGHT 500 Lumen "Mt.Bike" for under 10 bucks by Veggiecycle
I tried both just for giggles after I found my set up. The nice part about all of this is it will work now and even when you get your motor.
The only advice I can offer you is...get some Locktite! I didn't at first and it was scary to be riding along and the exhaust just falls off. =( I got home to find out the nuts vibrated loose and right down the studs. So yeah Locktite helps.
Other than that the Gurus of this forum have you taken care of. You know this forum is like that insurance company. I have never been in better hands.