Exhaust temps, valve shims?

[tryoun]

Alright the hesitation issue is fixed, now I'm trying to get my exhaust temps in order. All 4 pipes are all over the place ranging from 570 to 714. Adjusting the mix screws I got the 714 down to around 640 and now thery're all around 640 and I can't seem to bring the temp down any further. Off the bat I considered backing the clip off of the jet needle one notch to richen it but after some research I'm finding out that my valve clearences might be the culprit. I've been on her for 2 years now and the tap from the valve cover has gotten more noticeable. Any thoughts?