f250 2008 replaced HPFP. Can not get started. Certified ford Machanic working

What is your question?

Pulled truck to change oil and fuel filters. I did get air into lines but we have since bled. Could not get fuel pressure up. Replaced low and high pressure pumps. Now we can't get truck to start. My Machanic is ford certified. We can only get 270-300 psi on computer. Any suggestions ?