If it is the seal between the oil pan and the bottom of the timing cover then just pull the oilpan and replace the gaskets. I replaced mine with a one piece (Milodon I think) reuseble one (see pic). Should be easy to clean up the area where the gaskets meet if you use the original gaskets/rubber seal.
If it's the front crank seal you'll, as forest mention, have to pull the balencer and the timing cover, as the seal insert from the inside of the cover.
Kristian
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