Okay so get ready for this....
I finally get my engine back and spent all weekend putting it in. I break in the cam properly etc etc. The engine seemed to be running fine considering the timing isnt really tweaked or anything like that. I go for a test drive and about 10 miles into it I hear what sounds like a small exhaust leak from the header, varying with rpm and what not. My header gaskets blow out all the time so I think nothing of it. Another 5 miles down the road and the sound has gotten REALLY loud, and it actually sounds metallic, like two metal pieces are colliding repeatedly. The engine starts to stall so I pull off the road. I got the car back home to my garage and start pulling off the valve covers thinking it dropped a valve. All the valves are in place. I can't pinpoint the noise and the engine runs really sluggish and the noise is LOUD. Like with the rhythm of an exhaust leak but with a clank to it.
Upon installation of the headers I noticed there is not much clearance between the slave cylinder mounting flange and the header. It makes a loud clanking noise if you tap on it with the palm of your hand but it didn't make any noise on its own during warm-up or during test driving. To me it seems like this is a possibility for the noise source but the motor would have to be rocking very sharply and very hard for that to be the case. otherwise, I have some serious internal damage again. What steps should I take to pin point the issue? I drained some oil and it looked fairly normal. Pulling the pan is next but I have to wait until the weekend when I have time.