I've seen references to this, but is there a DIY for cutting the runner with a good write-up and pictures?

 

I never wrote one, but I do have pics and it's not too difficult with the right tools... rotozip & cuttoff wheels

 

I shaved the runners 1 3/4" on my old '01 5.9 and it was a nice mod. I used a saw zawl to get the meat of it cut out and then used a dremel and rotozip for the fine edging.

As for rockers, I had the Crower 1.7 rockers. The only thing I had to do for them was to pull the valve covers off and smush the oil baffle a little. I put a 2x4 across it and hit it with a hammer. That allows the rockers to clear. Next to the B&G flashed pcm I had, those rockers were the biggest performance enhancing mod I had put on. What a difference!!!