For most of the USGS 7.5 minute maps the NAD setting you will need to use for the continental United States is "1927 CONUS". In order to use the UTM grid system, you will need to connect the blue tick marks that are along the sides, top and bottom of the USGS maps. Notice that the blue tick marks aren't always parallel with the lines of Longitude and Latitude, on the map. If you need further assistance, the USGS people have a free packet, explaining how to use the UTM grid system, and they are now recommending that everyone using the 7.5 Minute USGS maps, having the capability, switch their GPS unit to the UTM mode. The phone number to reach them is: 1-888-ASK-USGS. (1-888-275-8747).
Check out the "MAP TOOLS" link at the bottom of the page. On this site, the author gives you the option of buying or making your own map tools. I printed some of the grid readers onto transparency film and I am very happy with the results. Just make sure that the transparency film you use is compatible with your printer. Some transparency films are designed for specific printers and inks, and may not work well with all brands. The transparency film I used was "3M Universal, Ink Jet Transparency Film." It gave satisfying results with my Canon BJC-620 printer, using Canon ink. The print would not wash off, with water.
Some older GPS units read only in Longitude and Latitude, including mine. If you have one of those units, go back to the Latitude & Longitude, navigation page.
Since my sole purpose, in writing these pages, is to further other's
ability to navigate into unknown areas without the fear of getting lost
I will continue to add information that I think might be useful. One thing I can tell you for certain; if you do your
homework, carry a USGS topo map of the area you're in, tools for figuring
your coordinates/locations and a working GPS unit, you don't have to fear
getting lost.
Reading UTM Grid On 7.5 Minute Map
Global Positioning System Resources
GPS Navigation,
Using Coordinates Of Longitude & Lattitude