What's the cheapest way to run all these F15T8 fluorescent tubes? Answered

I have a bunch of F15T8 fluorescent tubes, and I want to make my own light fixture with something like 4-8 of them running at the same time.

Doing some research has shown me that I need a ballast. Nearly all of the ballasts I found online for f15t8 were only for 1 or 2 lamps, and I don't really want to buy more than one. Is there any way I can use a ballast rated for a higher watt bulb or something? What happens if you put a F15T8 in a F32T8 ballast?