TF 727 late upshifts

Hi everybody,

I have overhauled my automatic transmission from my '84 GW with alot of help from some youtube videos and reading the manual from Carl Munroe. Result: The transmission shifts smoothly through all gears, but I can't get early shifts. So if I cruise at 25 mph it stays in second gear and 3th gear kicks in only from 40 mph. I have measured the line pressure which is 5 BAR (72 psi) which is too high, default should be 57 psi. Checked and cleaned all valves in the VB if they move freely. I have turned the line pressure adjusting screw (in valve body) almost completely out (clockwise)to lower the pressure but it remains at 72psi. I have adjusted the throttle rod complete to bottom end at WOT, and different steps in between. No result! I drove the car with throttle rod disconnected and it still shifts up at the same speeds.
Now I can try to find a weaker spring for the line pressure so it lowers the pressure, or I can install a weaker spring in the Governor. I am now doubting what I should do. Did I do something wrong? Why has the throttle rod no influence on the shift moments? Who is experienced and has some tips for me? Thanks alot in advance. best regards from the Netherlands Marc