6.1 Swap Won't Rev Past 3K HELLLLPPPPP!!!

Some may know the build but here are the particulars. 06 6.1 Hemi backed by a 727. Aftermarket harness built by who knows. Using the 04 APPS so we could attach a kick down cable for the 727. Street and performance ECM. The car runs great until you get to 3k rpms then hits a rev limiter? In park, neutral, or in gear its the same. I have run the calibration between the APPS and the throttle body with success, using the latest Snap On scanner. For the life of me I cannot figure out what the problem is. I am trying to get some contact info for the guy that built the harness, but haven't had any luck. Has anyone experienced this problem? Any ideas? Any help is much appreciated!