VZ LS1 4L60E to T56 swap – Cruise only works in 1st-3rd

[Panda53]

Hi all,

I'm very new to all this and I have been playing around a little with my VZ to help understand things a little deeper.

I’ve converted my 2004 VZ Calais LS1 from a 4L60E to T56 with 3.73 diff. P59 with OS 12592433, and I’m using PCM Hammer, PCM Logger, Universal Patcher and TunerPro.
I’ve segment-swapped TransCal and TransDiag from a manual Monaro bin I found online and corrected the speedo. Everything runs fine with no DTCs, Traction Control and Cruise Control were my only gremlins. After using claude to help me update the effective gear ratios, Traction Control was all sorted.
Cruise control remains my only problem. Cruise works perfectly in 1st, 2nd and 3rd at any speed and RPM, but won’t engage in 4th, 5th or 6th at any speed or RPM. The Tech 2 disengage history shows “Hi PCM Inhibit” (value 16 in PCM Logger). Brake and clutch inputs switch correctly, and the Current Gear PID reads 3 all the time.
I have been using claude to help me identify potential causes and generating segment swaps on several bins to road test. I've just about flashed the entire monaro bin to the PCM and still hasn't resolved the cruise issue. I also have a 2004 CTS-V manual bin that I crosschecked with the monaro bin and they seem to be consistent with each other.
The old 4L60E range switch wires are also left open at the gearbox end. Could this be a potential problem?
Hoping someone on here has had similar issues and might be able to point me in the right direction.
I'm also curious to know,
What controls manual gear detection and cruise inhibit?
What a factory manual VZ has on the range switch inputs?
It would be very handy if anyone has a stock VZ V8 manual bin on 12592433 that they wouldn't mind sharing.
I'll attach the original auto bin and current running bin if anyone wants to look at it.

Thanks in advance.