Cylinder has spark but not firing..

I really don't think the OP is listening to what is being told to him, for what to check. Pull the VC off rotate the motor and see if both intake and exhaust valves move. if they do, losen the shafts and see if it runs. If it does you will need to shim the shafts as told many posts ago. If the rockers do not move as much as the others on the head I would suspect a wiped cam, especially if you keep changing things around that do not work properly together.
Are the plugs on the cylinders in question oily? If you think the intake is cracked on the underside of it, while running it will also pull oil into the cyl.
You are making this much harder than it really is, to fix this car.