I have mounted my tank, a 16 oz by the way, using foam to cushion the base and top and used zip tie anchors epoxied to the side of the fuse. They are available at home depot. They have a 4-way slot for the tie and they either screw on or self stik adhesive. I epoxied mine onto the fuse about 1/2 way up. Zip tie goes over the top of the tank and foam and holds it nicely.

You'll probably need to push the tank as far forward as you can so the gear bolts clear on the inside. I hope you have used 2 or 3 1/4-20 nylon bolts to mount the gear, VF says they no longer ship these without the nylon gear bolts. I glued a couple of 1/8" ply plates to the bottom of the fuse over the gear and extended the plates forward a couple of inches to form a base for the tank as well.