Today I replaced the thermostat again and I am getting it all back together. It's a little tougher now working in the cold. My garage isn't insulated or heated, and with the wind chills near 0 right now, it makes for slow going. After cleaning everything up well with brake cleaner and compressed air, it looks like I still have an oil leak at the back of the engine underneath, but I can see now that it seems to be coming from the corner of the oil pan closest to the driver. Looks like I will be dropping the pan as well before all of this is done. Ford recommends a product like Permatex "The Right Stuff" to seal the oil pan with, correct? Should I used the black, or the import light grey?