Not clear from what you wrote that you need to be able to do:
1. Do you want the GPS before you to to the cemetery, so you can locate a particular grave?
The easiest is to get a friend with cellphone to load the BG app and go with you to the gravesite.
2. If you can't do that, open the cemetery map and zoom in as close as you can. You won't see the GPS numbers as BG hides them (for good reasons, I think). But -- then open a regular google map in a new window and find the cemetery on it. Zoom in on the approximate location of the grave you need and get it as close as you can. Then you can get the GPS numbers for that position on the google map, and you can put a locater pin there, so you can use the google map at the cemetery, if you can access it from some device, or copy the GPS numbers to a GPS enabled locater (in the car) so you can drive as close as possible to the grave and then walk and search.
Hope this helps. If not, reply back with a little more clarity of your question/issue and we will try to help.