Following on from my earlier post.
I broke up the Airfix Scout model, luckily without damage. I reduced the width of the two body halves by about 3mm each side. I then cut them into three as the length had to be reduced by about 2.7cm, I reduced the tail by about 1cm and the body by the rest. The main and tail rotors, engines and other components also reduced in size.
Ther main difference between a Scout and a Wasp is the Wasp has a wheeled undercarriage and the Scout has skids. This inlvolved some head scratching as the body also had a wedge shaped box and wing stubs to support the rear undercarriage.
The final conversion is shown here. I'd be the first to admit its not totally accurate in its proportions, but for what I need - mission accomplished.