1971 c10 coverted to R134 pressures too high?

[bautino95]

Hi. I recently converted my AC to 134. Clean and flushed everything. Recalibrated my POA valve. And got a new compressor. Pulled vacuum and leak check held good. Started to charge system with 12oz. Cans of r134. Only got 2 full cans in and some of a 3rd can. I stopped charging the system because the pressures are too high. I was having about 35psi on the low side and 325psi on the high. It was about 90* outside and I had a fan blowing on the condenser and engine rpm about 1000 rpm. I cant remember off the top of my head but I think I added 3 oz of PAG oil to the system when I redid everything . I'm thinking I need a new thermostatic expansion valve or POA valve. Looking for advise on trouble shooting.
Thanks