Hello and welcome to Just Answer I would be happy to assist you.
The only thing I can reccommend is to double check the valve cover gasket. That is the only place it can leak from. In my experience those gaskets are tricky to puy back on. Did you replace it with a new rubber gasket? Did you use any tube sealant? If there is sealant inbetween the rubber gasket and the valve cover it will continue to leak. If you are 100% certain without a doutbt the valve cover gaskets are good, then I would focus on checking the distributor oild seal as this will also leak. Let me know if you have any further questions. If not be sure to Accept, you can continue to ask questions related to this problem.