I usually try to shoot for 5-8 degree rise in temp in the 1/8. 15 is not to bad. Did it change this year since you say you ran these jets last year? What I'm getting at is could the fuel pump have changed on you. Don't know if it is electric or belt drive. Was there a fuel pressure change this year under power? If it were fuel pressure related jetting up will usually cause the problem to get worse on the big end because you can empty the bowls faster and the pump can't keep up, so I don't know that it is that just something to think about.
By the way, looks like you have a very strong combination there. I have a 383, 11.3 compression, Track1s, .600-.640 282-290 106lsa with an older Rupert and I have .168" jets in it. I know it is not apples to apples but just a comparison. I gain right at 5 degrees with it in the 1/8.