[jwheel55]

Guys! I removed the new starter motor this morning and did a check. The marking on the pinion teeth shows that it is meshing at least half of the length of the teeth and reasonably deeply. On the original it looks as though the whole length of the teeth have been in mesh.
The pinion isn't travelling too far and bottoming out. Just the opposite in fact so shimming isn't required. I spoke to the suppliers and the engineer from the company said it was possibly design differences of the bell housing and plate as the starter was more suited for a 302 than a 289. It's difficult to compare the old and new starter motors because they are so radically different in size overall. But it can only be a few thou difference but enough to cause noise during cranking. Like I said originally, it engages every time ok and spins the engine fine. It's just the noise it makes doing it. Guess I will have to live with it or try a OE starter. Thanks for your input . Jonny.