What he said ^...If the leak is between the timing cover and the block, you're going to have to pull the balancer to remove the timing cover. When you get the gasket kit it will have a new crank seal. Do it right, and replace your old one when you put it all back together. Torque wrench is your friend.
Ford also had a habit of using Metric head fastners with SAE threads (5/16-18) on certain areas. I can't recall the exact size (IIRC 10mm?), but I replaced all of mine with ARP products. Except for the two 'special' bolt/studs used for accessorie mounting:
Of course, it's much easier to do with the motor out of the vehicle