06 electrical or worse?!

[PHenslee]

Just within the past couple days I've had a few issues: slight shaking just above idle( I can let off the clutch a little and that's when its worst). The noise that accompanies the shake is real low pitched. I installed a magnaflow 5 inch turbo back a few weeks ago and one of the hangers would occasionally tap against the other on my truck(factory hanger). I used a thick hose to wrap one of them and stop the noise until I could fix it. So I assumed the recent noise was from them contacting. But now my factory tach reads 500rpm at idle and may even go to 450. The tach on my bullydog outlook shows 748-754, with no jumping or dropping. So I was planning on bringing it to the shop tomorrow. Now, on the way back from work tonight, I adjusted the bullydog down a level with the outlook. As soon as I did that, it almost died on me(lights shut off,rpms dropped to I'd guess 150 or so) but then it kicked right back to normal 750 idle. It was exactly as if I turned it off, but just before the engine settled, turned it back to run. No smoke, no power loss,boost normal,egt normal, oil presure normal. I believe its in my sig but I have a bddl w/ crazy larry,cfm+ intake tube, s&b intake, and southbend confe. Had a quadzilla boost fooler but took it of recently. PLEASE HELP ME OUT GUYS...