hi i have just aquired an old tamiya fire dragon which i'm very excited about, unfortunately when i connect the battery smoke come from the speed controller and the battery gets really hot and melts the wires, i am a complete novice to this but want get the old beauty working, could you advise on what the problem is please

Before connecting, you have not checked? It is important to check, it is clear that a short circuit due to damage.

your +and -are backwards. need a new esc now.

These ESC's run on smoke, when the smoke leaks out the ESC is broken.

you must have done something really ridiculous. check your ESC.