Without juice, I ran 13.8 @100. Thats with stock 6.0, stock manifolds, stock tune, stock converter and a 3.70 gear, 28 inch tire. I need to update my signature... Last year I ran a 12.6 @109 with a 100 shot, but everything else was the same, even the tune.
What I'm hearing from you is, Do the converter at the same time as the cam? I do have a taller first gear which should hurt matters.... But I'm 4080 pounds with me in it, on a small tire and reasonable gear. I would think I could get away with it. I think I could get low 12's if not high 11's with a stall, as my 60 foots have NEVER dipped below 1.9's

 

Thats weird you're cutting a 1.9x 60' but your times are identicle to mine with a higher trap speed. I must make up some land in the mid range with the shorter 2nd gear of the 60e, but it doesnt add up. It's amazing what a few pounds will get ya... it took me all the bolt on mods, a cam and NNBS intake to get me to a 13.8

I would be ecstatic if I could drop mine down to 5000 with me in it.

You don't HAVE to get a converter, but the cam would definitely like it. With this cam, a 3000 stall, and traction your 60's would probably drop by at least 2 tenths if not more and I picked up almost 4 MPH on my trap speed. Put it this way, with the 60e and a 258mm 3200 I was gunning for a low 1.8 to high 1.7 coming from a current best of 2.12. With slicks I see you cutting a 1.6x possibly.