I inject mine, and put them on the smoker at 11:00 pm at 180 until they reach 145-150 which is usually around 6-7:00 am. Then I turn it up to 225 and start spritzing. I don't like spritzing before the rub gets a chance to really set in.
I bought the same rack last month. I still have not used mine yet either, but I am impressed with how it looks. Hopefully soon I will be doing a couple batches of jerky to test it out.