I modified the hairlines sideburn to sideburn on two full caps with excellent results.

this unit started out with no recession and no temple points-





This is an all french lace unit, and all I did was cut out the recession and temple areas with an x-acto knife, then I used a pair of eyebrow tweezers to pluck back individual hairs to give a natural, staggered look.

Now most of these hairs were ventilated single strand with a half knot and the hair was a little weak to begin with (plus the base is strong) so I just started plucking away and the hair came right out without leaving any sort of knot behind, but if the hair is thicker and stronger, you might have to do as MB and others suggested and wet the hair beforehand to weaken it sufficiently that it comes out without leaving half of a hair or a knot behind. Just have to try it and see what works. You will also have to be more careful with swiss lace...