I think if your careful it could work better than silicone. not real crazy about silicone... it's also messy, doubt it would hold up over time. supposedly flex seal wont fail in any way due to sun damage. It wont be pretty (...thought out application will pay off), but will be effective i think. Im thinking a flexable wide weather stripping with a good tape on half of it that could overlap / protect the old rubbers enough could be a good way to go & wouldnt look to ugly? No matter what you use, you should clean up the area with rubbing alcohol or similar stuff, so you get max sticking power.