Don't mount it to your D700 until you verify that it can Safely mounted. This is a pre-AI mount. You would probalby have to have the lens converted so that you don't damage your camera.
Bjorn has a review on the AI-S: http://www.naturfotograf.com/lens_tele.html which is probably pretty similar to the AI mount. Seems like a very nice lens (I would love one )
I have & use a Sigma 400mm 5.6 and find it a very useful lens but would expect the Nikkor to be capable of much better IQ. A magnifying eye piece might help in the MF department. Good luck with it and carry on where grandpa left off. Take care. bob