You need to check if you have injector pulse and fuel pressure. Also if you have access to a scanner it would be helpfully to know any stored codes (if any).
Major cause of no spark in a junk yard motor would be the lack of oil pressure to the chain tensioner, you might want to try and put a manual oil pressure gauge on the engine to see if your oil pressure is coming up.
Lack of oil changes causes these motors to sludge-up, oil pressure drops & the oil driven timing chain tensioner lets the timing chain go loose enough to cause the Cam/Crank sensors to lose sync.This will set a code by the way.
How far did you tear the engine down??
Please post back, I'll try to help.
I'm buckling down for a blizzard here in down state NY
The reason I ask if you have spark and injector pulse is that when certain things are missing it will point you in an orderly direction from a trouble shooting stand point.