Keith , I am at exactly the same stage. I have taken the wings and rear valence off for repainting and am about to start at the rear. I bought the beading from Dave Kreisel so it is wrapped with Everflex. I have marked the halfway point and intend to start at the rear valence and work forward. I intend to punch oversize holes in the beading where the screws go through (using the rear valence flange as a template) and probably cut from there to the edge of the beading so that it can be slid into place after the valence is screwed halfway. That's the plan. I will probably proceed along the same lines with the rear wings. This means I start with a straightforward bit.
You will probably notice that you have to slim down the beading toward the front of the body when fitting the front wings as the lip that you screw into is narrower than the beading. At the moment I'm against fixing the beading first as it gives no room to adjust it in case it doesn't look right! I may change my mind of course.
As far as getting the beading around the corners I may phone Dave for advise as he was very helpful when I bought the beading.
Incidentally the stuff I took off the car was made with a vinyl cloth wrapped around three core lighting flex.
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