[Donunder]

The pin style, or lift at dot, is fine for around the cockpit and along the top of the dash, and you need one flat push button type on the door about a third of the way back from the leading edge. I'd avoid the cap style--they look too obvious when the cover is in place, although their mounting posts are smaller.

Ask your upholsterer to sew in some foam padding where the tonneau goes along the top of the door to compensate for the "dip" between the dashboard and the hip in the bodywork past the trailing edge of the door. It doesn't need much, and in fact I wouldn't have thought of it, but my guy suggested it to give the appearance that the cover was sitting flatter and to prevent the need to put more than one push-button stud in the door. The padding stops excess flapping when driving along and also makes the cover more water/dust proof.

You probably don't need as many clips around the back as shown in your third shot. I'm of the same opinion as Leroy on that it's a shame to destroy the clean lines of the bodywork, but it's a necessity to have a tonneau because there's not always cover when you're out somewhere. At the same time, try to avoid the picket fence look by keeping the number of clips down to a functional minimum.