Use a small-diameter chainsaw file and carefully file a small notch in alignment with the slot in the connecting rod. If you file from the inside to the outside of the bearing, you'll be less likely to raise a burr that could score the crankshaft. When the oil hole in the crankshaft aligns with the slot in the bearing, it spits a little oil onto the cylinder wall. The primary purpose of the hole is to keep the piston skirt from scuffing while the engine is loaded heavily.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!