So i've concluded that i need a new wire harnes after setting several differant codes for differant systems and replacing most said part parts with no improvement.

Ive got an 87 4runner 22re that is cali emision. My question is would i be able to swap in a fed emissions and be ok? or will that just not work?

 

You should be able to swap the engine harness and ECU. That's not too hard (relatively) I'm not 100% sure but I wouldn't think that you would have to mess with your body harness. Just make sure it's from a similar year as the one you have. It would be best for you to find a harness that you can pull yourself and take pictures of everything as you take it off so you know where everything is going to go on your engine and also what of the California emissions you can get rid of.
I've swapped a few engine harnesses and didn't have too much trouble with it. If the harness is of a different year just make sure the ECU pinout is the same for your body harness. You can find all the wiring diagrams and pinouts online. Just google it. Good luck!