Sorry....misread it at first.
I would think that re-painting the whole decklid would be the best way to make it look good...especially since you are dealing with black. I'm not a painter though. If it were my car I would want the whole decklid done.
2SS | M6 | VR w/White Stripes | 1 3/4" KOOKS - 3" Magnaflow | LPE 3.91 gears | ADM tuned | Halltech w/ADM Scoop | Spohn/BMR Trailing Arm/Toe Rod | BC Coilovers| Pedders FE4 ZL1 swaybars | Cradle/Diff/Radius Rod bushings | VMax TB | Morimoto Projectors | MGW shifter | Red Calipers