Ive been filling and sanding the door and quarter panel gap on my 68 firebird. Goal of Sanding and filling to get the door and qtr to fit flush..... well the edge of the door and the qtr are now sharp after the bondo and sanding so how do I get the nice rounded shaped edge? Im using a flat board and 80 grit and I just cant seem to get the edges "uniformly rounded" along the length of the door edge and along the length of the qtr edge. I'm doing this edge rounding right after Ive epoxied and filled and sanded to 80 grit smooth.....should I wait to round the edges after Ive applied some 2K and am using 180 grit.....or? Looking for some tips on what works best for some people......Im getting frustrated with my attempts.