Map won't align due to half squares

The maps I am trying to upload use a standard grid but were meant for printing so they have a half square all around the edge.  I cannot crop this out to make it fit because 1) the grid lines for the top of the map are invisible as they are over black space and 2) cropping out the half square would erase part of the image that is needed for the tiles to fit together.    Is there any way to get this map to actually work on roll 20?

Set your grid up to half scale (35 pixels = 1 unit) The tiles will snap to every half square. You can change it back when you are finished.

You can always use alt while dragging the map to make the full squares line up correctly and have the half squares leave a little bit of blank room around the edge of the map.

Kieth I ended up figuring out the half square trick I was looking in the settings and notice it.   Thank you though for responding, it's a great idea no matter who thought of it.

I can't claim credit for it. Half my ideas are just remembering other peoples' solutions.