Sanity Check Please

[old_master]

When diagnosing DTC's, always start with the first one. Repair the problem, then recheck the OBDII system to make sure the DTC does not reset. If more show up, start with the first one again, and so on. DTC's do not tell you to replace a part, they tell you what circuit to check.

P0151 indicates low oxygen sensor voltage. It refers to the sensor in the passenger side exhaust manifold.

P0147 indicates a problem in the oxygen sensor heater circuit, for the sensor located behind the catalytic converter.

P0300 is random multiple cylinder misfire. Meaning more than one cylinder misfired.

I'd be very skeptical with their diagnosis. Cylinder #1 is on the driver side and none of the DTC's singled out that cylinder, only a random misfire. #6 however is on the passenger side, but again, none of the DTC's singled that cylinder out either. You might want to get a second opinion. It's next to impossible to completely diagnose all malfunctions correctly, without following the proper diagnosis and repair procedure for each DTC.

[Blutarski]

I completelt agree with you suggestion, if you have a place that can read those codes for you quickly. I got the list, looked them up and went to town.
The Pass side O2 was replaced and it helped a little.
I also looked at other people's issues and their solutions were all over the place, so I was really trying to shoot in the dark.
I cleaned the intake VERY well, and I have to believe that the amount of crap in there had something to do with it. I also replaced the #1 and #6 injectors. I'm still not 100% how they cooked up those two but they were afforable and I didn't want to be in this situation again. When assembling, I cleaned every component, including the MAF sensor.
TA-DA!
The SES light stayed on for about 20 miles, which I assumed was leftover from when I pressuized the fuel system w/o the intake attached(to confitm no fel leaks). But the light went away, and no issues in about 300 miles.
I really appreciate the help and hopefully this thread will be helpful to other too.