Maybe my spot drill bit could do that .
Got the rest of the windows cut out & mounted the side panels to the bottom corner bars today (they both still need to be filed smooth & to the guide lines) but on 1 side the helicoils aren't working as they should so before things get anodised I'll need to fix this by either drilling the helicoils out all the way through the corner bars & then putting longer helicoils in or drilling holes for m4 helicoils & bolts, the side panels are essential to function spot on, sure I could relocate them but then there will be un-needed holes & I don't want that similar thing happened with my first scratch build & won't let that happen again , I'll try longer helicoils first but I won't be able to buy them until next week.