Hmm after hearing the video, I don't think it's in the head, although I could be wrong.

I am starting to suspect the harmonic balancer pulley or one of those bearings is making the noise.

I am not 100% but I couldn't hear the noise being influenced by revs. If it were valves, it would sound like a drum line snare solo in your valve cover.

I'd say inspect Water Pump/Harmonic Balancer(damper)/ alternator

And the belt that controls them. Although its not going to be the belt.

Either way though, the motor, for the most part sounds pretty smooth. She's pretty quiet.

This post was edited by OldAndyAndTheSea on Jan 25 2013 09:05pm

Strange coincidence! A guy I used to work with had me help him diagnose a simlar noise in his SB 350. His was in a 1500 truck, but it sounded EXACTLY like that.
It ended up being that one valve spring was starting to give too much. He replaced them and it ran great for a few months until a throwout bearing gave out on him while on the highway.

was in ontario today and listened to the engine with a long screw driver, was my first time doing it so I wasnt sure wat to expect.
i did not find that ticking sound but i did notice the driver side head had more of a rumble going on then the passenger witch seem to be in sinc with everything else i tried listening.
i guess i wont know until i open the valve covers, i might of gotten better results if i had listened from the rear of the block but i didn't feel like taking the console out after all the suspension work.