[exlrrp]

As I recall, we used decimals to fill in the gaps between gridlines, using the basis of reading right and up. the decimals were eyeballed.
By that way, , on your map,. "Culvert" for example, would have been at: 33.6 46.2
LZ "Selluger (sp?) would have been at: 36.3 45.7
Thats the way they taught it in Recondo School

But we had a better way than just giving it in the clear:
There were designated reference points that had been decided on before the unit went to the field. These were arbitrary and had names like: Beer, Cars, football tems etc. That way you could use different names for the same thing: Budweiser, Coors, Michelob for beer, Ford Chevy or buick for cars, Fortyniners, Packers or Cowboy for football tems. This means you never used the same name twice for the checkpoint, ideally to foil detection.
We never thought that maybve there was some Vietnamese familiar with our country but we were wrong--Ho spent a year here and was addicted to Camels for example
Lets say the reference point is the grid crossing atL 35 44, we'll call it "cigarettes."
So the locaation of LZ Selluger would be given as : "From Marlboro, up 1.8 right 1.4"
or "Culvert:" "from Pall Mall up 2.2 left .8"

Seems like a much easier way than you describe
Good to see you back Ron'
Stay good
James