Pump regulator adjustment

Hello gentlemen I am wondering if any of you have any thoughts on how to set the pressure on the regulators on a 4300c linkbelt I am getting an engine bog issue when I pull in the dipper in. I have good fuel pressure new filters and no junk in the fitting at lift pump. I have 4000 psi at both pumps ,dipper will relieve at 4500 psi on in and out . My pilot is 580psi. How is best way to tell if pump is at full swash,and are the regulators something to consider. Kinda a grey area for me....

Pump regulator adjustment

Pump regulator adjustment