Alky6
150cc
I think I got it. Will try again in the morning. Created a viewport that is 34 x 185, brought the drawing up to 1:1 in the viewport and will print it again from there. I'm willing to expect 1/4-1/2" off but 3" is too much.
Don't accept a 1/4" either. In your viewport double click to get to model space. Type "zoom" then type "1/1xp" and hit enter - that will give you a 1:1 scale within your viewport. You can use "pan" to move the viewport around, but don't scroll your mouse button. Then either lock the viewport or click the button in the lower right part of the screen to toggle back to paper space. Obviously, if you wanted a 1/10 scale you would type "1/10xp"