I've seen several
HID power supplies from cheap kits blow chunks.
Most quit burning once the fuse blew.
I'd make sure the power supplies were protected, I used a couple radio shack project boxes to provide a out shell of protection from water and road slime.
I used the black ones with an aluminum face, that way the supply could be against the AL and get rid of heat. Only tried this on 1 car so far we shall see....
Dave