09 prostar horrible Mpg

[earnies2]

I had really good milage after the mandate was done. Then I broke a exhaust valve the shop rebuilt the head new valves seats and guides. They also put a new turbo, injectors, and new rod and main bearings. The truck ran horrible after the repair. I ended up replacing all 4 actuators and one injector was leaking down , now the truck runs good but I have poor milage loaded I get 5.5 to 6.2 driving 62-65. I checked with Rawze after the work was done and he checked my program and said it was good that was a year ago I wonder if there are any updates since then. I am also wondering if I should bring it down from 565 to 525? Would changing the injectors help.... the milage is killing me. Thanks in advance