OBD2 Port Help?

[bbluma]

Hey yall, hope I don't sound too much like an idiot here but got a question or two about OBD2 ports. So Im working on my 66' c10, and PO had swapped it with a driveline out of a 1999 Tahoe. So engine was starting to run bad right before we started the upgrade of new fuel lines and a EFI setup pump/tank. Seemed like it was starving for fuel maybe, started popping really bad, and kinda just running in and out.

My question is this, we haven't been able to find the OBD2 port anywhere, and I assume the PO just cut it out. Where does it run back into? And is it possible to run another one? Reading the codes would make diagnosing the engine a whole lot easier. If it is a dumb question you can say it haha, im just curious if its possible.
Thanks.