I'm making some assumptions about where you are hiking and what conditions you will be faced with, so feel free to correct me.
Mountain west, highs around 80, lows near freezing?
I know you mentioned being on a budget in another thread, but that military sleeping bag is probably going to be worse than useless. heavy, cold and soaks up water and never drys, it's cotton right?)You can find a much lighter and still fairly cheap (although not 20$) options. Lafuma bags spring to mind, heck someone here is posting a homemade climashield quilt for 55$ shipped for like 22oz.
take that weight savings and take some kind of minimalist tarp or a ponch tarp (golite ones sell used on here for
35$ normally.)10 oz, it's still lighter than that bag.
I am assuming if you're in Idaho, you are going to be in the mountains, and it never hurts to assume that mountain weather will get squirrley from time to time.
also, aqua mira is your friend, so light, especialy in microdroppers. I would switch out the camelback for a platty big zip, and add a bike bottle or platty sport bottle (Like to have extra water container, just in case)