You spun a main bearing, how the hell did you do that?? 9 times out of 10, unless you have super high miles, the rod bearings are what get spun. I have 2 vehicles at my house right now, both with spun rod bearings. You can fix that for about 30 bucks, replacing all of the rod bearings, but generally when you spin a bearing, you can not get away with only bearings. How did he come to the conclusion that you spun a bearing? If you spun a bearing, your oil pressure would be much lower. Also, the colder the motor is, the quieter the noise will be. Basically meaning that thicker oil will hide the sound. A ticking sound is NOT a rod bearing, and especially not a main bearing. Those are more like a muffled thud kind of sound, very deep, not a ticking sound. Since youre valvetrain just got redone, I can almost guarantee that something is not right in the top of the motor, like an improperly adjusted rocker, or a lifter tick. I would not purchase a new bottom end until you get the opinion of someone who will not make money off of you, like a knowledgable motorhead who could care less what the problem is, and is not looking to get a crap load of money in labor by repairing/replacing your motor. Thats my .02.