bought a mini cat a few years back from a different member here. been working on it off and on for the whole time. finally getting near the end and its time to gel the bottom half. the boat was painted with bright white paint and then a graphic painted over the white. the gel under is kinda an off white. i have a handful of glass repair spots that need finish on them, scratches in the sponson corners that will be repaired and sharpened, remove the hook on the center, chips in the paint, and since i want a different color, figure i should just gel the whole bottom when its time. i wanna use black. do i want a smooth surface to shoot the gel over or do i want a porous surface so it can grab more area? ie 1000 grit or 100 grit? most of the boat is smooth but the paint chipping off seems it wont make a good base for gel to go over. using a sand blaster to get the paint off but its also making the surface rougher. closer to a 100 grit finish. any tips you can toss my way. thanks