Little more work, but this lets you design your fretboard to your specs. Now you can print this out on glossy paper and embed it under plexiglass, or you can print it out on waterslide decal paper and apply it directly to the guitar, or you can print laminate and double-stick tape to your guitar.

I'd suggest beside open G and open E tunings, that you consider C6/Am7, which is bass to treble. This sounds like it could be a very good learning tool, especially if it can be applied and removed without harming the instrument. (If the images don't want to go over the fretlines, right click the image and choose 'Size and Position', click Text Wrapping and choose 'In front of text'.) Topic: Lap Steel Fretplate (fretboard Template) Plans. In Word, you can draw over the fretlines and add your fret markers.

Set the number of strings to 0 to just print the fretlines. Set the string widths to be equal (unless you want some taper in your strings) Enter your scale length (I use 23 inches, other common scales are 22.5 and 24 inches).

Lap steel fretboard template