This is a simplified diagram showing how to connect the fuel lines to a tank that can be installed inside the car, to make it more shock-resistent. Below are some pictures of the modified Kadett in which we used this design.

The tank without the modified cap holding the fuel lines. The ties holding the tank in place may not look very professional, but they are efficient.

The cap of the tank was drilled through to admit both fuel lines and was then sealed using a two-component putty that is fuel-resistent.