2000 mustang rough idle p0174 code

ok so i did a valve job bank 1 on this 2000 mustang 3.8 because one of the valves got bent it set not running for about 5 years when i got it back together it would not start i decided that it was the fuel pump that was bad because you could not hear it come on at all when you switch the key on so it set for about 2 months before i replaced the fuel pump and drained and cleaned the gas tank out i noticed that there was a lot of trash in the bottom of the tank and some clear flakes that i assume was the gas turned to lacquer. i got the pump in and started it up and took it for a ride i found it had a horrible hesitation while accelerating and the idle was rough so i took it back home and checked the plug wires and took it out again for a longer ride about half way through i got a check engine code when i got back home i hooked up the scanner and it gave me a p0174 code lean on bank 2 so i cleaned the maf sensor and checked for vacume leaks bye spraying starting fluid on connections and around the intake manifold and started it up again and erased the code but still idles rough with a miss so i decided to pull the wires off the coil one by one and there is no change in idle when i unplug cylinder # 6 wire so i am thinking it is the injector on cylinder 6 because that would coincide with the code i got i think what do you guys think? please let me know if i am off in my assumption.