For the fueling jug I use this hardware set: [link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXJ811&P=0]LINK[/link]
Its pretty easy to install and use and shouldn't require any glue. As for what you may want to have in your flightbox, here's a list:
1) Rubber bands (if your plane uses them)
2) Extra fuel tubing
3) Assorted screwdrivers and wrenches. I prefer to have those that are necessary to work on the plane's fittings.
4) Glow plug wrench
5) Propeller nut wrench (NOT the same as your four-way wrench. I carry a spanner for this)
6) Spare propellers.
7) Expanded Scale Voltmeter (NOT an option)
8) Fuel pump, starter/chicken stick, igniter
9) Spare glow plugs
10) Pliers (I scored a very nice little 6-piece set at Harbor Freight. They've been a lifesaver more than once already)

Additional items you may consider having:
Glue, paper towels/rag, extra clevises/control horns, any parts that you find breaks often on your craft, extra nylon bolts for wings and landing gear, quick charger that runs on 12 volts, large garbage bag (just in case ).

Hope this helps.