I would have thrown in what Barrman said...although probably not as well said as he did....
That is the sum total of the topic over the last 20 years of real world experience and discussion.
Its a good tcase to a point...that point is where the old flat head engines with their limited rpm potential end and the modern, ohv, motors with higher rev potential start. The NP200 was designed for the flatheads...the NP202 and NP205 were designed for the ohv types...with the NP202 being scarcer, larger and higher rated. Either will work in the M715 as both have been used.
This is the easiest, most durable and least long term problems solution to the NP200's propensity for heat creation.
Lord send your Holy Ghost into our hearts and make the desire of our hearts Your Will.
Pro-choice, that's a LIE, babies don't choose to die!!