Interested in hearing about your results. I've been happy with JB4, Map 7 and the 50/50 WMI, but often wonder if the Lap 3 stage 2.5 would be worth it. Good luck. Unfortunately I'm not an expert in all of this. Darrin,
@AWDGT2, has always been my go to guy for any JB4/WMI adjustments. Maybe hit him up. He's super knowledgeable on all this.
Thoughts...
I believe the JB4 will behave exactly the same as it shouldn't realize you have a new ECU tune.
If you don't have a catless downpipe then you shouldn't have any issues with overboost.
You should be able to fine tune your boost using map 6, i.e. add a lb here or there, if you are not peaking as high as you like.
Looking forward to you posting logs and your thoughts.