Hi Jay,
The actual 100% [Whizzer]correct light for your Whizzer is either the Bendix generator, large headlight, and Whizzer taillight or the Hall generator, large Chrome headlight, and Whizzer taillight. The system was often tagged with the name "Bi-Lite".
Because your Whizzer is a vintage 1949 model either is correct because the Bendix system was offered along side the 1949 Hall system for a period of time. The Bendix generator attaches to the screws that hold on the belt guard, the later Hall unit is held in place by the exhaust manifold mounting bolts.
I will include a picture of the light [available via Memory Lane]. Another photos will show the mounting brackets attached, and the last picture displays the light mounted on a 1948 Pacemaker using the Bendix generator [look at the belt guard].
Of course the most popular and common was a chrome headlight with 2 "D" batteries and was normally attached to the handlebar pinch bolt. I don't have any pictures of that setup, but do remember them well.
Have fun,
