Ok I finally got it work out and how to do the black out the edges on the Marguard lexan windows.
After a lot of time and money, trials and F ups. I can't believe how something so simple can be such an ass pain.
You start be tracing the edge of the window flange on to the window with a non permanent felt pen. I did mine on the outside of the window.
Then flip it over I used fine line masking tape to copy it on the the inside of the window.
Sand the edges with a scotch brite pad then clean with mild soap and make sure its dry.
Check and make sure the tape is still sticking and you want to paint this soon after you had masked as the tape will let go in the tight corners after a day or two.
Using window primer, I used (Sika Primer-207) bought from a auto glass shop, paint the black on, starting at the masking tape edge and go all the way around the tape then stop and quickly remove the mask as the primer will be come stringy real fast and look like pizza being pulled apart making a mess of your nice sharp edge don't worry if you get a few of them. Once you have all the masking tape off go back and finish painting the rest of the area you want blacked out but DO NOT go back over area you have already done it will make a mess. after 15 mins go back and push any stingy bits back sharping up the line with your finger nail then leave it for a day or two to set up real good.
Go back re-mask your edges and repeat it take two coats for total black out and non scratch border. Also when putting on the second coat it will melt into the first coat so DO NOT not go back over it as it will make a mess if you need to touch up wait a day or two and go lightly.
Doesn't look great on the inside but the door will hide it, but most importantly it wont come off just from wiping it.