hello sammy

i think this will solve your problem , it is called " folower tank "
http://www.rcscalebuilder.com/forum/...82&PN=1&TPN=11

look at this post of mine and roll down , not the first draw but the second one , you will see drawing of one 4oz tank near the engine and big tank in the wing on the CG line .

this will work fine for your plane
cheers - cobi