P0306 have changed everything that is stated including both cats, still there

Don't mean to be disrespectful but changing parts with out properly testing is a good way to change unnecessary parts and a wait of your throwing away money. I see it too often that to avoid seeing a mechanic shop a lot of mechanically inclined people try to fix cars themselves and don't get me wrong some things can be done in a driveway with no problems but some require proper equipment that's very pricy and knowledge. Changing very expensive CATS with out knowing it would solve my problem would mean i get a law suit dropped in my lap. So Pushrod is correct in his statements. I recently had a ford that was doing the same thing as you are describing. Misfire code but we had good spark no other codes and injector sounded as if it was injecting fuel. the injector was covered by the intake so we opted to remove the injector in question and swap it to a more accessible injector location this way if the misfire now changed to the new location of the injector we knew the injector was at fault. and in our case the fault did travel to new injector location witch was located where in less then 5 min we can change it. your truck has a much better set up and that allows injectors to be changed way faster then the ford i mentioned. that would be where i would start. further with proper equipment i can get bidirectional control of the outputs of the computer and command injectors to be disabled to confirm cylinder contribution. there is a lot more to it but If you want my shop is located in cape coral and we will more then happy to sort it out for you.

IF compression is ok .. Cylinder # 6 fuel injector OR fuel injector 'circuit' fault is most likely suspect .. Test for injector pulse using a noid light or stethoscope... Old school stethoscope is a 'very long' screwdriver, put blade onto injector and ear on handle and listen for injector clicking .. IF clicking can be detected, suspect clogged injector! .. Can listen to a 'know good' injector on another cylinder and compare sound... *Sometimes* lightly taping on injector with screwdriver tip will help, it might even start working again! .. NOW, you stated the "crank sensor" was replaced ... Then don't forget about the *required* crankshaft position variation re-learn proceedure!! .. Good luck with it!