Just purchased this loco, my 5th in the collection, and want to change the stack and piping.
The stack is easy but I am not sure about the piping supplied.  It's obvious to me that the pipe that went around the baloon stack has to go and the supplied pipe seems to fit around the boiler and up to the top of the new stack.
Is this where the new piping goes?
How much of the old piping must be removed?
Where is the new piping installed?
Where do I find information on doing this modification?
Why are these instructions not provided with the model??

All help appreciated

Vroc3349