Engine replaced, No spark or start since!

95 Altima 2.4
I replaced motor with one that just ran 4 days ago, now all of the sudden theirs no spark, but all the lights, light up, and it cranks, new coil, distributor, power transistor, what the hell I can't figure it out, went over grounds and plugs twice.
..........Tried to reset the Ecm but theirs no cooperation. At least I see no red light down their. Help Please I've read this on other threads but no response back then.

Battery good I'm running out of ideas any one............

thanks shannon