Most tanks slide in from the front now.  Usually in the old days we put them in from the bottom on inverted engines.  Do a search of some of the construction photos on this site.   Also Walter Umland has some photos on his builtrightflyright site.

ive been doing control line for a couple of years. i now scratch building fancher twisters i know how a tank mounts on a profile.  but how do you guys mount the tank in a full fuse stunter ?

I've tried many different ways to mount a tank: hooks and rubber bands, soldered ears, through the fuse with a stop on the inboard. All have pluses and minuses but I found one that works for me. It requires no soldering, simple to make and includes full tank adjustability. It involves marine sealant(sometimes called fishtank sealant) and three pieces of  1/8 plywood.  Here's how it works:

The attachments for the tank are glued onto balsa fuse side before the model is covered.

1) Get marine sealant at a local Home Depot(paint department) or an Automotive store. Something that looks like this:
http://syampolsky.fotki.com/model-airplanes/kmd-stunt/img-0261.html

2) Cut out a piece of plywood that is as tall as the fuse-facing tank wall and 3/4" wider. Previous picture shows the part next to the tube of sealant.
http://syampolsky.fotki.com/model-airplanes/kmd-stunt/img-0254.html

3) Scoff fuse facing wall of the tank with some 120 grit sand paper and degreas it with acetone then alcohol.
http://syampolsky.fotki.com/model-airplanes/kmd-stunt/img-0262.html

4) Cut two identical pieces of plywood that are as tall as the back plate and about 1/2" wide. Drill a hole in the center of them and insert a 2-56 blind nut.
http://syampolsky.fotki.com/model-airplanes/kmd-stunt/img-0259.html

5) The two pieces will be attached to the fuse with 5 minute epoxy. Before you glue them on, bolt both of them onto the back plate so that you will have them spaced exactly as needed. In the previous photo one of the pieces was already bolted on. Using 5 minute epoxy, glue the two pieces onto the fuse making sure you don't accidentally glue the backplate. Since you we are using the blind nuts, the pieces need to be pushed into balsa crushing it a little.

6) After the glue has dried, unbolt the backplate from the fuse, apply some marine sealant onto the tank wall and press it against the backplate. Use scrap stick of wood to remove all glue that squeezed out. If no glue has not squeezed out, you did not apply enough of it. There is no need to weight it down, just put it on the backplate and let it dry for 24 hours. After the glue has dried, the tank is ready to be mounted. Here's the end result:
http://syampolsky.fotki.com/model-airplanes/kmd-stunt/img-0287a.html

I have a tank that was attached in this fashion back in 2003. It still works very well. Apparently marine sealant is impervious to our fuels. Oh, and one more thing: brush some epoxy to fuel proof the plywood plate otherwise it will soak up the oils and eventually fail.