Glad to hear you got your problem solved Tim!
The burnt CEL circuit in the PCM is a problem that I never used to see but is becoming more common. Sometimes the trace is burnt on the board and sometimes the transistor for it is bad. Either way, it's a cheap fix.
VSS has almost no effect on tuning. The only thing that it is good for is to prevent stalling when coming to a stop with a manual trans. I can tune the stalling out if there is no VSS, but I definitely recommend keeping VSS with a manual.
In a situation like this with an unknown cam and injectors that lack tuning data, I would not opt for a mail-order tune. Instead, I would remote tune it.
With remote tuning, I am only dialing in the idle in real-time. After that, I show you how to datalog. You basically hit record and go out and drive it using real-world scenarios. The file that it spits out gets emailed to me. I review the file and modify the tune which I email back. That process repeats a couple of times until the numbers look good on my end and you are happy with it on your end. Then I buy the tuning hardware back and send the final tune to you on a permanent chip.
The biggest advantage a dyno has is that it is a safe environment to go wide-open throttle. It's also nice to have RWHP and TQ numbers, the tuning software is only able to calculate flywheel numbers but both are still good for bragging rights. The dyno provides better repeatability for WOT pulls, but street driving provides for more accurate loading that the vehicle will actually see, especially with how much 1 bronco can vary from another. So any good dyno tuner should actually spend more time driving it on the street and just using the dyno for WOT pulls.
