i did this about a month ago too. i use all of them when the van sits inbetween camp trips, but i use the one for the front window all the time. they are really handy, but i noticed that the one i cut out for the windshield is actually shrinking. so if your going to do this, make the one for the windshield a little bigger than you normally would
im also too lazy to remove the rearview mirror, so one small slice in the center and its easy enough to install from stop to stop for daily use. i did use packing tape to reinforce around the cut so it cant rip though. it does let a little light through, but if its light out, i wanna be up doing camping crap anyway, lol.
I also used packing tape for little tabs so they have a spot to pull on for eazy removal. kinda hard to tell in pic, but you get the point.
they are really nice camping when its hot out. suprised me the first time i used it to keep cool up camping. some strategic parking and these covers, and its really easy to keep the inside considerably cooler.
i went and bought a thermal heat lazer gun dealy at harbor freight to see how much the temps are down using reflectix covers vs not, but we havent had the same temps/conditions 2 days in a row for exact measuring for weeks, but the temps have ranged from 5 degrees cooler to 15 degrees cooler, depending on weather of course.
one 25' roll did all 6 doors and the windshield with a 5' piece leftover. took me about an hour by myself. super easy to do and Im really happy I took the time to make the covers.