Jan, I am still looking for a particular paper on the Peters and am trying to call my sis in NY. If you take a look at a map of Highland Falls, a bit NE of Crandberry Pond is where the large tract of land that was held by Peter and another parcel east, closer to the river. Neighbors being J P Morgan and the Pell's. I know that there was a younger Peter (son?)that held this land later and believe he owned a livery stable supplying horses for West Point. It is this info I am trying to get from my sister when she returns from her vacation.
I also know that the earlier Mandigos are overlooked in the 1790 census because of the spelling. I assume they saw the cursive "g" as a "z" and were enumerated as Mandazoe or Mandizoe. This family intermarried with the Jaquish ( Jaques, Jaycox etc) Faurot and Weyant families. Again your Conklin name is an old prominent surname and they lived very close by. There is a woman on this forum I have been helping with the surname Vought( related to these Conklins) who may be of help. If you are having any problems finding John or Luke in the censuses, it's just the spellings. You will find them under Mandago, Mandego and I have even seen it as Mandigeau. Just be creative here. Give me some more time and I will try to get all I can. Please e-mail me at firstname.lastname@example.org