Also, ten years of crap and condensation on the bottom of the oil pan will be the first thing sucked up when you crank it over.
Do yourself a favor and drain the oil and stick your finger in the drain hole to determine if it feels muddy or just oily. If muddy, drop the pan and clean it first. If oily, stick fresh stuff in there and give the engine a try.
The excitement of hearing an old machine run can quickly come to an end when you hear bearings squeal for mercy.