Help! with making 150w light?!?!?!

Hiya
Im setting up a 150W hps/mh light.
Ive bought this ballast:
http://cgi.ebay.co.uk/ws/eBayISAPI....95354&_sacat=See-All-Categories&_fvi=1&_rdc=1

Thought i could just get a lamp holder and rig it up but now im being confused with ignitors and capacitors???
ive read that Metal halides at least dont need an ignitor?
very very confused and really don't want a fire hazard.
Any help would be great as time is running out for my baby.

I know hps uses ignitor, but im not sure about the halide, I think I read somewhere you can make a ballast switchable by putting a toggle switch on the igniter, but im not sure about your ballast. mine are for hps only and I didnt do the toggle switch thing, I am with ya man, it is real confusing shit if you dont speak "electrician". sorry if that didnt help, good luck