The PB Blaster did the trick, I turned the idle screw a bit with the intake tube off and the blades appeared close from the start and remain closed... TP (%) signal went from 19.2 down to like 18.6, not sure how much adjustment is left and has me wondering if the sensor is bad? I know you had to adjust the older 79-95 sensors, not sure if the 96-98 are adjustable?
I did get my front NGK 02 Sensors installed first start up was still rough idle, but I'm assuming there is some amount of time for the PCM to register and adjust. Because the second time I started it later in the afternoon the idle was much smoother... Being the scientist I am, in between the two start-ups I replaced the vacuum line between the intake plenum and BOV/Boost gauge connection and deleted the driver PCV out of it, as well as tightened the connection at the throttle body, so it's impossible to isolate what the issue may have been.
I found out the AEM wideband gauge is old enough it uses the Bosch LSU 4.2 sensor, so I'll have to return the 4.9 I had ordered. Can't find any cheaper alternatives that I trust so probably going to have to drop $80 on the real deal Bosch unit, if anyone has used something else that's cheaper with good success please let me know.
Finally struggling to figure out the proper fine tuning of the clutch cable. Getting quite a bit of chatter at the release point. Struggling to figure out how much it should be tightened at the clutch fork vs. fire wall adjustor. Suggestions on that would be appreciated otherwise I'll just take it to the local Mustang shop, because I really want it dead on for good drivability and to not damage the clutch.
Here's a couple pictures including the fog light re-pin: