Originally Posted by PeterAlway

The Nike motor was surplus military hardware, and as pointed out before, you couldn't just extend it. That said, there were Nike payloads that had a cylindrical section above the motor, including the 2nd stage payload of the Nike-Nike Smoke. And I have seen photos of high-power models of the Nike Smoke that had an added section (electronics bay or somesuch) that extended the length of the model body. That model wasn't accurate, but maybe that got stuck in your head.