After the bird strike, the boroscope would take probably 6-8 hours to do, engine cool, panels off, rummage around, diagnose and panels back on, then normally a ground run to establish all ok. This is assuming that in Buttholeville in the Land of Bumbly Boo there is a qualified engineer and the relevant inspection kit to hand.
Frequently there is no damage found, but traces of blood can give the game away. In simple terms the greater the mass of the bird the larger the damage/potential damage, with a single hit. Also frequently the smell of burning flesh/roast chicken type smell gets in to the cabin through the aircon systems, so the pax/cabin crew might be aware before the flight crew, if no engine indications vary. A bird strike can also damage subsequent systems, for example an aircraft recently is suspected to have lost hydraulic fluid due to a bird hitting the noseleg, and rupturing a hydraulic pipe leading to loss of steering (not 757) on landing, so theres plenty of potential for a 'simple' bird strike to have significant consequences as part of a sequence of events.
Try typeing 'bird strike' into photo search on airliners.net to get some idea of damage etc
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