Thank you. Is the install really as simple as removing the top end of the door trim nearest the plastic triangle? These items are super expensive in the UK (shipping from the USA is $40 alone on top of the $79 for the item) and I don't want to end up buying this and bottling out.
You need to check on the 'AWE Tuning' UK website, they have a store near Manchester and online facility. My knowledge is that they are easy to fit on the Boxster/Cayman 981 and the 911 991.2. For the 991.1, different story, you have to strip out the door panel and air bag cover to get to the retaining screw. For the 718, I don't know but I would be pretty sure you have the simple not complicated access to the retaining screw. I bought mine online for a 991.2 from the UK AWE store. There should be a little fat black triangle thing on the inside (see first photo) behind the bigger flat triangle on the outside which you are replacing. You just prise off easily the inner triangle (from the bottom up as per instructions included) to reveal the one retaining screw.
They do make a difference but don't completely eliminate buffeting with roof up but one window or both down or half way down. The Blackmill ones just stick over the top and according to posts on the Rennlist 911 site they work better (have a bigger lip) but don't look so neat. They're also dearer at $130 online especially when you then factor in delivery cost from the US as not available anywhere in UK. The AWE ones are about $79 online from the US but then delivery on top and you can get hit for import duty too. So the UK AWE ones are our only real option. Mine were £90 (rip off Britain as usual) plus £8 delivery from their website, the only supplier available.
I must say I don't think I would bother again. They are much thinner, flimsier and cheaper looking than the bits they replace although not noticeably so when fitted. Close to £98 is ridiculous but I guess they are low volume plastic pressings so no economies of scale. Come in a nice box though with instructions and a free lollipop.