When doing banners for the front window just measure across and find what fits best for your liking from left to right. for height. I would say cut something out that is the height you want and put it on the windshield. My truck said DODGE on the front when I got it. I pulled it off the same day. Because at 6'2" I couldn't see stoplights or anything like that because the letters blocked it.

 

haha luckily im only like 5'5 so i mean i think a 5"H and a maybe idk 50"W would be a good look

 

just get some tape and run some strips across the windshield and remove them one at a time from the bottom up until you feel you found the hieght you like.