I noticed a different note and a rough idle so I bought new spark plug wires and changed them. I had the firing order wrong at first, then corrected it when I heard/felt the misfire. I started it back up and it still had the same symptoms and now some smoke. There was oil on the header. See the picture.
Can I fix this by changing the gasket or is this a job better left to a shop?

 

Pulling the headers is a simple affair, I definitely wouldn't pay somebody to fix it. It takes less than an hour to replace those gaskets.

 

Ok, thanks for the advice. Is there any type of gasket that I should use or is OEM good enough?

 

I'd do a little more diagnostics before taking it apart. Something is leaking oil on the header. Your headers may indeed have leak, but that wouldn't explain the oil on top of the headers. I'd clean everything up with simply green and a toothbrush and see if the source of the oil leak becomes clear. Chances are it's coming from the cam tower in one way or other -- e.g. gaskets/seals on the end or the main gasket for the tower. Any chance you got oil on it when working on the motor? Although possible I suppose, oil and exhaust leaks don't generally create a rough idle. That's more likely to be a vacuum leak or sensor. The factory/Victor Reinz gaskets should be fine for the headers and cam tower if it comes to that...

 

The oil is not from any recent work and that was the first and only time I have seen smoke and oil. It looked to me like it came from the gasket. What else could be e culprit on the rough idle at warm up? Once it's warm it idles normally

 

It was the spark plug wires. I put the new ones on correctly this time and it has solved the issue, for now. Not sure where the oil came from; maybe the violent misfiring when the wires were wrong.

 

a couple of cans of brake cleaner will make short work of the oil , dirt and debris. After its clean, watch closely and find the leak. Simple green and a tooth brush will work well, but is tedious and time consuming .