Was the fuel leak in the passenger side, usually the inlet side for the carb. As rbohm said it may not be oil. Leaking fuel mixing with grease, dirt and grime on your engine can produce a thick oily substance, giving the impression of an oil leak. It also could be a clogged PCV valve. I've had one clog up and force oil out of the dipstick from the crankcase pressure. It ultimately ruined my alternator, before discovery on a long trip.
chevy runs deep, Don't step in chevy!
289 - Holley 4150 570cfm; Performer intake; mild cam; MSD HEI; 302 heads; Roller Tips; Hedman Tri-Y headers; H-pipe w/Flowmaster 40's; 9 in posi 3.50; 205/50-17F; 225/50-17R.